تهجين

‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫‪Part(1):Introduction of Coordination Chemistry‬‬ ‫ﻣﻘﺪﻣﺔ ﺇﻟﻰ ﺍﻟﻜﻴﻤﻴﺎء ﺍﻟﺘﻨﺎﺳﻘﻴﺔ ‪-:‬‬

‫‪Coordination or Complexes Compounds‬‬ ‫ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ‪:‬‬

‫ﻳﻣﻛﻥ ﺃﻥ ﺗﻛﻭﻥ ﺍﻟﻛﻳﻣﻳﺎء ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ﻫﻲ ﻛﻳﻣﻳﺎء ﺍﻟﻌﻧﺎﺻﺭ ﺍﻻﻧﺗﻘﺎﻟﻳﺔ ﻷﻥ ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ﻫﻲ ﺍﻟﺗﻲ ﺗﺣﺗﻭﻱ ﻋﻠﻰ ﺃﻳﻭﻥ ﺃﻭ‬

‫ﺫﺭﺓ ﻓﻠﺯ ﻣﺭﻛﺯﻳﺔ ﻣﺣﺎﻁﺔ ﺑﻌﺩﺩ ﻣﻥ ﺍﻷﻳﻭﻧﺎﺕ ﺃﻭ ﺍﻟﺟﺯﻳﺋﺎﺕ ) ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ( ﻭ ﺃﻳﻭﻥ ﺍﻟﻔﻠﺯ ﺍﻟﻣﺭﻛﺯﻱ ﺍﻟﻣﺗﻣﺛﻝ ﺑﺎﻟﻔﻠﺯﺍﺕ ﺍﻻﻧﺗﻘﺎﻟﻳﺔ‬
‫ﺃﻱ ﻋﻧﺎﺻﺭ ﺍﻟﺭﻛﻥ ‪ d‬ﺃﻭ ‪ F‬ﺍﻟﺗﻲ ﺗﻛﻭﻥ ﺫﺍﺕ ﺧﺻﺎﺋﺹ ﻣﻐﻧﺎﻁﻳﺳﻳﺔ ﻭ ﻁﻳﻔﻳﺔ ﻣﺧﺗﻠﻔﺔ ﻟﺫﻟﻙ ﺳﻭﻑ ﻧﻬﺗﻡ ﺑﺷﻲء ﻣﻥ ﺍﻟﺗﻔﺻﻳﻝ ﻓﻲ‬

‫ﺩﺭﺍﺳﺔ ﺧﺻﺎﺋﺹ ﺍﻟﻔﻠﺯﺍﺕ ﺍﻻﻧﺗﻘﺎﻟﻳﺔ ‪.‬‬

‫‪Transition Elements‬‬ ‫‪≠∫WO�UI��ô«  «eKH�«-‬‬

‫ﻳﺣﻣﻝ ﻣﺻﻁﻠﺢ ﻓﻠﺯ ﺍﻧﺗﻘﺎﻟﻲ ﺗﻔﺳﻳﺭﺍً ﻗﺩﻳﻣﺎً ﻳﺗﻣﺛﻝ ﺑﺎﻻﻧﺗﻘﺎﻝ ﺑﻳﻥ ﺍﻟﻌﻧﺎﺻﺭ ﺍﻟﻣﻣﺛﻠﺔ ﺫﺍﺕ ﺍﻟﻛﻬﺭﻭﻣﻭﺟﺑﻳﺔ ﺍﻟﻌﺎﻟﻳﺔ ﺟﺩﺍً ) ﻋﻧﺎﺻﺭ‬
‫ﺍﻟﺭﻛﻥ ‪ ( S‬ﻭ ﺍﻟﻌﻧﺎﺻﺭ ﺍﻟﻣﻣﺛﻠﺔ ﺫﺍﺕ ﺍﻟﻛﻬﺭﻭﻣﻭﺟﺑﻳﺔ ﺍﻟﻭﺍﻁﺋﺔ ﺟﺩﺍً ) ﻋﻧﺎﺻﺭ ﺍﻟﺭﻛﻥ ‪ ،( P‬ﺃﻣﺎ ﺍﻟﺗﻔﺳﻳﺭ ﺍﻟﺣﺩﻳﺙ ﻓﻳﺳﺗﻌﻣﻝ ﺑﺷﻛﻝ‬
‫ﺃﻭﺳﻊ ﻟﻳﺷﻣﻝ ﻋﻧﺎﺻﺭ ﺍﻟﺭﻛﻥ ‪ d‬ﻣﻥ ﺍﻟﺟﺩﻭﻝ ﺍﻟﺩﻭﺭﻱ ﺍﻟﺣﺩﻳﺙ ﺃﻱ ﺍﻟﻔﻠﺯﺍﺕ ﺍﻟﺗﻲ ﺗﺣﺗﻭﻱ ﻋﻠﻰ ﺃﻭﺭﺑﺗﺎﻻﺕ ‪ d‬ﺍﻟﻣﻣﺗﻠﺋﺔ ﺟﺯﺋﻳﺎً ﺃﻱ‬
‫ﺃﻧﻪ ﻫﻧﺎﻙ ﺛﻼﺙ ﺳﻼﺳﻝ ﻣﻥ ﺍﻟﻔﻠﺯﺍﺕ ﺍﻻﻧﺗﻘﺎﻟﻳﺔ ﺗﺑﺩﺃ ﺍﻟﺳﻠﺳﺔ ﺍﻷﻭﻟﻰ ﺑﻔﻠﺯ ﺍﻟﺳﻛﺎﻧﺩﻳﻭﻡ ‪ Sc‬ﻭﺗﻧﺗﻬﻲ ﺑﺎﻟﺯﻧﻙ ‪ ، Zn‬ﻭﺗﺑﺩﺃ ﺍﻟﺳﻠﺳﻠﺔ‬
‫ﺍﻟﺛﺎﻧﻳﺔ ﺑﻔﻠﺯ ﻳﺗﺭﻳﻭﻡ ‪ Y‬ﻭﺗﻧﺗﻬﻲ ﺑﺎﻟﻛﺎﺩﻣﻳﻭﻡ ‪ ، Cd‬ﻭﺗﺑﺩﺃ ﺍﻟﺛﺎﻟﺛﺔ ﺑﻔﻠﺯ ﻻﻧﺛﻳﻭﻡ ‪ La‬ﻭﺗﻧﺗﻬﻲ ﺑﺎﻟﺯﺋﺑﻕ ‪ Hg‬ﻛﻣﺎ ﻓﻲ ﺍﻟﺟﺩﻭﻝ ﺍﻟﺩﻭﺭﻱ‬

‫ﺍﻟﺗﺎﻟﻲ‪.‬‬

‫‪1‬‬

‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫‪Electronic Configuration Of Transition Elements ≠∫ WO�UI��ô« dUMFK� w�Ë�J�ô« qJA�« -‬‬

‫ﻋﻧﺎﺻﺭ ﺍﻟﻣﺟﺎﻣﻳﻊ ﺍﻟﺭﺋﻳﺳﻳﺔ ﺍﻟﺗﻲ ﺗﺳﺑﻕ ﺍﻟﻣﺟﻣﻭﻋﺔ ﺍﻷﻧﺗﻘﺎﻟﻳﺔ ﻻﻳﻭﺟﺩ ﻟﻬﺎ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ﻓﻲ ﺍﻟﻣﺩﺍﺭ ‪ d‬ﻭﻟﻛﻥ ﺍﻟﻌﻧﺎﺻﺭ‬

‫‪ Sc‬ﻳﻣﺗﻠﺊ ﺍﻟﻣﺩﺍﺭ ‪ d‬ﻓﻘﻁ ﻣﺎﻋﺩﺍ‬ ‫ﺍﻷﻧﺗﻘﺎﻟﻳﺔ ﺗﺣﺗﻭﻱ ﻋﻠﻰ ﺍﻟﻣﺩﺍﺭ ‪ d‬ﻭ‪ S‬ﻓﻔﻲ ﺍﻟﺳﻠﺳﻠﺔ ﺍﻷﻧﺗﻘﺎﻟﻳﺔ ﺍﻷﻭﻟﻰ ﻣﻥ ﺍﻟـــ‪Zn‬‬

‫ﺍﻟﻧﺣﺎﺱ ‪ Cu‬ﻭ ‪ Cr‬ﺣﻳﺙ ﺃﻥ ﺍﻟﻣﺩﺍﺭ ‪ S‬ﺍﻟﺧﺎﺭﺟﻲ ﻟﻌﻧﺎﺻﺭ ﺍﻟﻣﺳﺗﻭﻯ ﺍﻟﻔﺭﻋﻲ ‪ d‬ﻳﻛﻭﻥ ﻓﻲ ﺣﺎﻟﺔ ﻁﺎﻗﺔ ﺃﻗﻝ ﻣﻥ ﻁﺎﻗﺔ‬

‫ﺍﻟﻣﺳﺗﻭﻯ ﺍﻟﻔﺭﻋﻲ ‪ d‬ﻟﻠﻣﺳﺗﻭﻯ ‪ n-1‬ﻭﻧﻅﺭﺍً ﻷﻥ ﺍﻟﺫﺭﺍﺕ ﺗﻣﻳﻝ ﻷﻥ ﺗﻛﻭﻥ ﺃﻗﻝ ﺣﺎﻻﺕ ﺍﻟﻁﺎﻗﺔ ﻓﻳﺗﻡ ﻣﻠﺊ ﺍﻟﻣﺩﺍﺭ ‪ S‬ﺃﻭﻻً‬
‫ﻭﻟﻛﻥ ﺍﻟﻧﺣﺎﺱ )‪ (3d104S1‬ﻭ ﺍﻟﻛﺭﻭﻡ )‪ (3d54S1‬ﻗﻳﺗﻡ ﻣﻠﺊ ﺍﻟﻣﺩﺍﺭ ‪ d‬ﺍﻭﻻً ﻷﻧﻬﺎ ﺍﻟﺣﺎﻟﺔ ﺍﻷﻛﺛﺭ ﺛﺑﺎﺗﺎً ﺃﻱ ﻋﻧﺩ ﻭﺟﻭﺩ‬

‫ﺧﻣﺳﺔ ﺃﻭ ﻋﺷﺭﺓ ﺃﻟﻛﺗﺭﻭﻧﺎﺕ ﻓﻲ ﺍﻟﻣﺩﺍﺭ ‪. d‬‬

‫‪Table: Electronic Configuration of first raw transition Metals‬‬

‫‪ -‬ﺍﻟﺧﻭﺍﺹ ﺍﻟﻛﻳﻣﻳﺎﺋﻳﺔ ﻟﻠﻌﻧﺎﺻﺭ ﺍﻷﻧﺗﻘﺎﻟﻳﺔ ‪-:‬‬

‫ﺗﺗﻣﻳﺯ ﺍﻟﻌﻧﺎﺻﺭ ﺍﻷﻧﺗﻘﺎﻟﻳﺔ ﺑﺧﻭﺍﺹ ﺗﻣﻳﺯﻫﺎ ﻋﻥ ﺑﻘﻳﺔ ﺍﻟﻌﻧﺎﺻﺭ ﻣﻧﻬﺎ ‪-:‬‬
‫‪ ‬ﺗﻛﻭﻳﻧﻬﺎ ﺣﺎﻻﺕ ﺗﺄﻛﺳﺩ ﻣﺧﺗﻠﻔﺔ ‪.‬‬

‫‪ ‬ﺗﻛﻭﻳﻧﻬﺎ ﺃﻳﻭﻧﺎﺕ ﻭ ﻣﺭﻛﺑﺎﺕ ﻣﻠﻭﻧﺔ ‪.‬‬
‫‪ ‬ﺗﻛﻭﻳﻧﻬﺎ ﻣﺭﻛﺑﺎﺕ ﺫﺍﺕ ﺧﻭﺍﺹ ﺑﺎﺭﺍ ﻣﻐﻧﺎﻁﻳﺳﻳﺔ ‪.‬‬

‫‪ ‬ﺗﻛﻭﻳﻧﻬﺎ ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻟﻣﻌﻘﺩﺓ ‪.‬‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫‪ ‬ﺣﺎﻻﺕ ﺍﻟﺗﺄﻛﺳﺩ ﺍﻟﻣﺧﺗﻠﻔﺔ ‪-:‬‬

‫ﺗﺗﺻﻑ ﺍﻟﻌﻧﺎﺻﺭ ﺍﻷﻧﺗﻘﺎﻟﻳﺔ ﺑﺗﻛﻭﻳﻧﻬﺎ ﺃﻳﻭﻧﺎﺕ ﻣﻭﺟﺑﺔ ﻓﻲ ﺣﺎﻻﺕ ﺗﺄﻛﺳﺩ ﻣﺧﺗﻠﻔﺔ ﻭﺫﻟﻙ ﺑﺳﺑﺏ ﺗﻘﺎﺭﺏ ﻁﺎﻗﺔ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ‬
‫ﺍﻭﺭﺑﻳﺗﺎﻻﺕ‪ ns,(n-1)d‬ﺍﻷﻣﺭ ﺍﻟﺫﻱ ﻳﺟﻌﻠﻬﺎ ﻗﺎﺩﺭﺓ ﻋﻠﻰ ﺍﻟﻣﺷﺎﺭﻛﺔ ﺑﻌﺩﺩ ﻣﺧﺗﻠﻑ ﻣﻥ ﺍﻹﻟﻛﺗﺭﻭﻧﺎﺕ ﻓﻲ ﺍﻟﺗﺂﺻﺭ ﺍﻟﻛﻳﻣﻳﺎﺋﻲ ﻭ‬
‫ﺍﺳﺗﻘﺭﺍﺭ ﺣﺎﻻﺕ ﺍﻟﺗﺄﻛﺳﺩ ﻳﻌﺗﻣﺩ ﻋﻠﻰ ﻋﻭﺍﻣﻝ ﻋﺩﻳﺩﺓ ﻣﻧﻬﺎ ﺍﻟﺗﺭﻛﻳﺏ ﺍﻻﻟﻛﺗﺭﻭﻧﻲ ‪،‬ﻧﻭﻉ ﺍﻟﺗﺂﺻﺭ ﻭ ﺍﻟﻛﻳﻣﻳﺎء ﺍﻟﻔﺭﺍﻏﻳﺔ ‪ ،‬ﻭﻳﻭﺿﺢ‬

‫ﺍﻟﺟﺩﻭﻝ ﺣﺎﻻﺕ ﺍﻟﺗﺄﻛﺳﺩ ﺍﻟﻣﺧﺗﻠﻔﺔ ﻟﻠﻌﻧﺎﺻﺭ ﺍﻷﻧﺗﻘﺎﻟﻳﺔ ‪.‬‬

‫‪Sc Ti‬‬ ‫‪V Cr Mn‬‬ ‫‪Fe Co‬‬ ‫‪Ni Cu‬‬ ‫‪Zn‬‬
‫‪1+ 1+‬‬ ‫‪+2‬‬
‫‪+2‬‬ ‫‪+2 +2‬‬ ‫‪+2‬‬ ‫‪+2 +2‬‬ ‫‪+2 +2‬‬
‫‪loss of ns e-‬‬ ‫‪+3 +3‬‬ ‫‪+3 +3‬‬ ‫‪+3‬‬ ‫‪+3 +3‬‬ ‫‪+3 +3‬‬
‫‪+4 +4‬‬ ‫‪+4‬‬ ‫‪+4‬‬ ‫‪+4‬‬
‫‪+4‬‬ ‫‪+5 +5‬‬ ‫‪+5‬‬ ‫‪+5‬‬
‫‪+6‬‬ ‫‪+6‬‬
‫‪+6‬‬ ‫‪+7‬‬

‫‪Loss of ns and (n-1)d e-‬‬

‫ﻭﻧﻼﺣﻅ ﻅﻬﻭﺭ ﺍﺗﺟﺎﻩ ﻣﻌﻳﻥ ﺧﻼﻝ ﺍﻟﺩﻭﺭﺓ ﻟﻠﻌﻧﺎﺻﺭ ﺍﻷﻧﺗﻘﺎﻟﻳﺔ ‪-:‬‬

‫‪ .A‬ﻳﺯﻳﺩ ﺭﻗﻡ ﺍﻟﺗﺄﻛﺳﺩ ﻟﻛﻝ ﺃﻳﻭﻥ ﺣﺗﻰ ﺍﻟﻭﺻﻭﻝ ﻟﻠﻣﻧﻐﻧﻳﺯ ‪ Mn‬ﻭﺑﻌﺩﻫﺎ ﺗﺑﺩﺃ ﺑﺎﻟﺗﻧﺎﻗﺹ ﻭﻳﻌﻭﺩ ﺫﻟﻙ ﺇﻟﻰ ﺯﻳﺎﺩﺓ ﺍﻟﺗﺟﺎﺫﺏ ﺑﻳﻥ‬
‫ﺍﻟﺷﺣﻧﺔ ﺍﻟﻧﻭﻭﻳﺔ ﺍﻟﻣﺅﺛﺭﺓ ﻭ ﺍﻹﻟﻛﺗﺭﻭﻧﺎﺕ ‪.‬‬

‫‪ .B‬ﻛﻠﻣﺎ ﺯﺍﺩﺕ ﺣﺎﻟﺔ ﺍﻟﺗﺄﻛﺳﺩ ﻛﻠﻣﺎ ﻗﻝ ﺛﺑﺎﺕ ﺍﻟﻌﻧﺎﺻﺭ ﺍﻷﻧﺗﻘﺎﻟﻳﺔ ﺧﻼﻝ ﺍﻟﺩﻭﺭﺓ ‪.‬‬
‫‪ .C‬ﺗﻣﻳﻝ ﺍﻟﻌﻧﺎﺻﺭ ﺫﺍﺕ ﺣﺎﻻﺕ ﺍﻟﺗﺄﻛﺳﺩ ﺍﻟﻌﺎﻟﻳﺔ ﻟﺗﻛﻭﻥ ﻋﻭﺍﻣﻝ ﻣﺅﻛﺳﺩﺓ ﺟﻳﺩﺓ ﺑﻳﻧﻣﺎ ﺗﻣﻳﻝ ﺍﻟﻌﻧﺎﺻﺭ ﺫﺍﺕ ﺣﺎﻻﺕ ﺍﻟﺗﺄﻛﺳﺩ‬

‫ﺍﻟﻣﻧﺧﻔﺿﺔ ﻷﻥ ﺗﻛﻭﻥ ﻋﻭﺍﻣﻝ ﻣﺅﻛﺳﺩ ﺃﻛﺛﺭ ﻋﻧﺩ ﺍﻻﻧﺗﻘﺎﻝ ﺧﻼﻝ ﺍﻟﺩﻭﺭﺓ ‪.‬‬
‫‪ .D‬ﺍﻷﻳﻭﻧﺎﺕ ﺑﺣﺎﻟﺔ ﺍﻟﺗﺄﻛﺳﺩ ﺍﻟﺛﻧﺎﺋﻳﺔ )‪ (2+‬ﺧﻼﻝ ﺍﻟﺩﻭﺭﺓ ﺗﻛﻭﻥ ﻋﻭﺍﻣﻝ ﻣﺧﺗﺯﻟﺔ ﻗﻭﻳﺔ ﻭﺗﺻﺑﺢ ﺃﻛﺛﺭ ﺛﺑﺎﺗﺎً ﻋﻧﺩ ﺍﻻﻧﺗﻘﺎﻝ ﻣﻥ‬

‫ﻋﻧﺻﺭ ﻵﺧﺭ‪.‬‬

‫‪ ‬ﺗﻛﻭﻳﻥ ﺃﻳﻭﻧﺎﺕ ﻭﻣﺭﻛﺑﺎﺕ ﻣﻠﻭﻧﺔ ‪:‬‬

‫ﺃﻥ ﺃﻭﺭﺑﺗﺎﻻﺕ ‪ d‬ﺍﻟﺧﻣﺳﺔ ﻟﻸﻳﻭﻥ ﺍﻟﺣﺭ ) ﺍﻟﺣﺎﻟﺔ ﺍﻟﻐﺎﺯﻳﺔ ( ﻟﻠﻔﻠﺯ ﺍﻷﻧﺗﻘﺎﻟﻲ ﺗﻛﻭﻥ ﺫﺍﺕ ﻁﺎﻗﺔ ﻣﺗﺷﺎﺑﻬﺔ ﺃﻱ ﺍﻧﻬﺎ ﻣﺗﺳﺎﻭﻳﺔ‬
‫ﺍﻻﻧﺣﻼﻝ ‪ degenerate‬ﻭﺍﻹﻟﻛﺗﺭﻭﻧﺎﺕ ﺗﺗﺭﺗﺏ ﻓﻳﻬﺎ ﺣﺳﺏ ﻗﺎﻋﺩﺓ ﺑﺎﻭﻟﻲ ‪، Pauli Principle‬ﻭﺗﺗﺄﺛﺭ ﻫﺫﻩ ﺍﻷﻭﺭﺑﻳﺗﺎﻻﺕ‬

‫ﺑﺎﻟﻣﺟﺎﻝ ﺍﻟﻛﻬﺭﻭﻣﻐﻧﺎﻁﻳﺳﻲ ﺣﻳﺙ ﻳﻛﻭﻥ ﺍﻟﻔﻠﺯ ﻭﻋﻧﺩ ﺣﺎﻟﺔ ﺗﺄﻛﺳﺩ ﻣﻌﻳﻧﺔ ﺍﻟﻌﺩﻳﺩ ﻣﻥ ﺍﻷﻟﻭﺍﻥ ﺍﻟﻧﺎﺗﺟﺔ ﻋﻥ ﺍﻣﺗﺻﺎﺹ ﺗﺭﺩﺩﺍﺕ‬

‫ﻣﺧﺗﻠﻔﺔ ﻋﻧﺩ ﺍﺻﻁﺩﺍﻣﻪ ﺑﺎﻟﻣﺎﺩﺓ ‪ ،‬ﻭﺗﺗﺑﺩﻝ ﺃﻟﻭﺍﻥ ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻟﻣﻌﻘﺩﺓ ﺑﺗﺑﺩﻝ ﺣﺎﻟﺔ ﺍﻟﺗﺄﻛﺳﺩ ﻟﻠﻔﻠﺯ ﺑﻣﺎ ﻳﻧﺳﺟﻡ ﻭﺗﻐﻳﺭ ﻋﺩﺩ ﺇﻟﻛﺗﺭﻭﻧﺎﺕ‬
‫‪ d‬ﻭ ﺍﻟﺟﺩﻭﻝ ﻳﺑﻳﻥ ﺍﻟﺗﺑﺩﻻﺕ ﺍﻟﻠﻭﻧﻳﺔ ﺍﻟﻣﻌﺗﻣﺩﺓ ﻋﻠﻰ ﺣﺎﻟﺔ ﺗﺄﻛﺳﺩ ﺍﻟﻔﻠﺯ ‪.‬‬

‫‪Oxidation state‬‬ ‫‪+2‬‬ ‫‪+3‬‬ ‫‪+4‬‬ ‫‪+5‬‬ ‫‪+6‬‬ ‫‪+7‬‬
‫‪Elements‬‬ ‫‪V+2‬‬ ‫‪V+3‬‬ ‫‪VO+2‬‬ ‫‪VO2+‬‬
‫‪Violet‬‬ ‫‪Yellow‬‬ ‫‪blue‬‬ ‫‪yellow‬‬
‫‪V‬‬

‫‪3‬‬

‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫‪Cr Cr+2 Cr+3‬‬ ‫‪CrO4-2‬‬
‫‪Blue green‬‬ ‫‪yellow‬‬
‫‪Mn‬‬ ‫‪Mn+2‬‬ ‫‪Mn+3‬‬ ‫‪MnO3-‬‬ ‫‪MnO4‬‬ ‫‪MnO42-‬‬
‫‪Pink red‬‬ ‫‪blue‬‬ ‫‪green‬‬ ‫‪violet‬‬
‫‪Fe‬‬ ‫‪Fe+2‬‬ ‫‪Fe+3‬‬
‫‪green purple‬‬

‫ﻭﻋﻧﺩ ﺩﺭﺍﺳﺔ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺑﺻﻭﺭﺓ ﻣﻭﺳﻌﺔ ﺳﻧﺭﻯ ﺃﻥ ﺃﺳﺗﺑﺩﻝ ﺃﺣﺩﻯ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﻓﻲ ﻣﺭﻛﺏ ﻣﻌﻘﺩ ﺑﻠﻳﻛﺎﻧﺩ ﺁﺧﺭ ﺃﻗﻭﻯ ﻣﺟﺎﻻً‬
‫ﻳﺅﺩﻱ ﺍﻟﻰ ﺯﻳﺎﺩﺓ ﻓﺎﺻﻝ ﺍﻟﻁﺎﻗﺔ ﺑﻳﻥ ﺃﻭﺭﺑﺗﺎﻻﺕ ‪ d‬ﺍﻟﻣﻧﺣﻠﺔ ﻭﺑﻬﺫﺍ ﻳﻧﺣﺭﻑ ﺍﻟﺿﻭء ﺍﻟﻣﻣﺗﺹ ﻣﻥ ﻣﻧﻁﻘﺔ ﺇﻟﻰ ﺃﺧﺭﻯ ﻭﻫﻭ ﺳﺑﺏ‬

‫ﺍﺧﺗﻼﻑ ﺃﻟﻭﺍﻥ ﻣﻌﻘﺩﺍﺕ ﺍﻟﻔﻠﺯﺍﺕ ﺑﺣﺎﻟﺔ ﺗﺄﻛﺳﺩ ﻣﻌﻳﻧﺔ ﻛﻣﺎ ﻓﻲ ﺍﻟﺗﻔﺎﻋﻼﺕ ﺍﻟﺗﺎﻟﻳﺔ ‪:‬‬

‫‪1- [Cu(H2O)4]+2‬‬ ‫‪[Cu(NH3)4]+2‬‬ ‫‪[Cu(CN)4]-2‬‬
‫‪Colorless‬‬ ‫‪Deep blue‬‬ ‫‪Colorless‬‬

‫‪2- [Cr(H2O)6]+3‬‬ ‫‪[Cr(H2O)3(NH3)3]+3‬‬ ‫‪[Cr(NH3)6]+3‬‬
‫‪Yellow‬‬
‫‪Violit‬‬ ‫‪Red‬‬

‫‪ ‬ﺍﻟﺻﻔﺎﺕ ﺍﻟﻣﻐﻧﺎﻁﻳﺳﻳﺔ ﻟﻠﻌﻧﺎﺻﺭ ﺍﻷﻧﺗﻘﺎﻟﻳﺔ‪-:‬‬
‫ﺍﻟﺷﺭﺡ ﺍﻟﺗﻔﺻﻳﻠﻲ ﻟﻬﺫﻩ ﺍﻟﺻﻔﺎﺕ ﺳﻳﺫﻛﺭ ﻓﻲ ﻣﺣﺎﺿﺭﺍﺕ ﻣﺗﻘﺩﻣﺔ ‪ ،‬ﻭﻟﻛﻥ ﺑﺻﻭﺭﺓ ﻣﺑﺳﻁﺔ ﺗﺻﻧﻑ ﺍﻟﻣﻭﺍﺩ ﺇﻟﻰ ﺑﺎﺭﺍ‬

‫ﻣﻐﻧﺎﻁﻳﺳﻳﺔ ﻭﻫﻲ ﺍﻟﻣﻭﺍﺩ ﺍﻟﺗﻲ ﺗﻧﺟﺫﺏ ﻧﺣﻭ ﺍﻟﻣﺟﺎﻝ ﺍﻟﻣﻐﻧﺎﻁﻳﺳﻲ ﻭﺳﺑﺏ ﺫﻟﻙ ﻫﻭ ﺍﻣﺗﻼﻙ ﻫﺫﻩ ﺍﻟﻣﻭﺍﺩ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ﻣﻧﻔﺭﺩﺓ‬
‫ﺣﻳﺙ ﺗﻌﻣﻝ ﻫﺫﻩ ﺍﻻﻟﻛﺗﺭﻭﻧﺎﺕ ﺑﻣﺛﺎﺑﺔ ﻣﻐﺎﻧﻁ ﺻﻐﻳﺭﺓ ‪،‬ﺑﺎﻻﺿﺎﻓﺔ ﺇﻟﻰ ﺍﻟﻣﻭﺍﺩ ﺍﻟﺩﺍﻳﺎ ﻣﻐﻧﺎﻁﻳﺳﻳﺔ ﺍﻟﺗﻲ ﺗﻛﻭﻥ ﺟﻣﻳﻊ‬

‫ﺍﻟﻛﺗﺭﻭﻧﺎﺗﻬﺎ ﻣﺯﺩﻭﺟﺔ ﻛﻣﺎ ﻓﻲ ﺍﻷﻣﺛﻠﺔ ﺃﺩﻧﺎﻩ ‪.‬‬

‫‪3d 4S‬‬

‫]‪Paramagnetic Cr : [Ar‬‬

‫‪4d‬‬ ‫‪5S‬‬

‫‪Diamagnetic‬‬ ‫]‪Pt : [Ar‬‬

‫‪ ‬ﺗﻛﻭﻳﻥ ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻟﻣﻌﻘﺩﺓ ‪ -:‬ﺗﻛﻭﻥ ﺍﻟﻔﻠﺯﺍﺕ ﺍﻷﻧﺗﻘﺎﻟﻳﺔ ﻣﺭﻛﺑﺎﺕ ﻣﻌﻘﺩﺓ ﺫﺍﺕ ﺧﺻﺎﺋﺹ ﻁﻳﻔﻳﺔ ﻭ ﻣﻐﻧﺎﻁﻳﺳﻳﺔ ﻣﻬﻣﺔ ﻭﻛﺛﻳﺭ‬
‫ﻣﻥ ﻫﺫﻩ ﺍﻟﻣﺭﻛﺑﺎﺕ ﻣﻛﻭﻧﺔ ﺿﺭﻭﺭﻳﺔ ﻓﻲ ﺍﻷﻧﻅﻣﺔ ﺍﻟﺑﻳﻭﻟﻭﺟﻳﺔ )ﺍﻟﻬﻳﻣﻭﻛﻠﻭﺑﻳﻥ )ﻣﻌﻘﺩ ﺍﻟﺣﺩﻳﺩ‪، ( Fe‬ﻭﺍﻟﻣﺭﻛﺑﺎﺕ ﻣﺿﺎﺩﺍﺕ‬

‫ﻣﺭﺽ ﺍﻟﺳﺭﻁـــﺎﻥ‪ cisplatin) (carboplatin,‬ﻛﻣﺎ ﻣﺑﻳﻥ ﺃﺩﻧﺎﻩ‪:‬‬

‫‪4‬‬

‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﻭﻗﺩ ﻳﺗﺑﺎﺩﺭ ﻟﻠﺫﻫﻥ ﺃﻥ ﻛﻝ ﻣﺭﻛﺏ ﻣﻛﻭﻥ ﻣﻥ ﻋﺩﺓ ﻋﻧﺎﺻﺭ ﻳﻌﺗﺑﺭ ﻣﺭﻛﺑﺎً ﻣﻌﻘﺩﺍً ﻣﺛﻝ ﺍﻟﺷﺏ ﺃﻭ ﻣﻠﺢ ﻣﻭﻫﺭ )‪ ( Mohr's Salt‬ﻭﻫﺫﻩ‬
‫ﺃﻣﻼﺡ ﻣﺯﺩﻭﺟﺔ )‪ (Double salts‬ﻭ ﻟﻳﺳﺕ ﻣﺭﻛﺑﺎﺕ ﻣﻌﻘﺩﺓ ‪ .‬ﻟﺫﺍ ﻳﺟﺏ ﻣﻌﺭﻓﺔ ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻟﻣﻌﻘﺩﺓ ﻟﻛﻲ ﻳﺗﺳﻧﻰ ﻟﻧﺎ ﺩﺭﺍﺳﺗﻬﺎ‬

‫ﻭﺗﻣﻳﻳﺯﻫﺎ ﺑﺎﻟﺷﻛﻝ ﺍﻟﺻﺣﻳﺢ‪.‬‬

‫ﺍﻟﻣﺭﻛﺏ ﺍﻟﺗﻧﺎﺳﻘﻲ ‪ Coordination Compound‬ﻫﻭ ﻣﺭﻛﺏ ﻣﺳﺗﻘﺭ ﻻ ﻳﻌﻁﻲ ﻛﺎﻓﺔ ﺍﻷﻳﻭﻧﺎﺕ ﺍﻟﻣﻛﻭﻧﺔ ﻟﻪ ﻋﻧﺩ ﺫﻭﺑﺎﻧﻪ‬
‫ﻓﻲ ﺍﻟﻣﺎء ‪،‬ﻓﻣﺛﻼً ﻣﻌﻘﺩ ‪ [Co(NH3)6]CI3‬ﻋﻧﺩ ﺫﻭﺑﺎﻧﻪ ﻻ ﻳﻌﻁﻲ ﺃﻳﻭﻥ )‪ Co(III‬ﺍﻟﻣﺟﺭﺩ ﻭ ﺟﺯﻳﺋﺎﺕ ﺍﻻﻣﻭﻧﻳﺎ ﻭﻟﻛﻧﻪ ﻳﻌﻁﻲ ﺍﻻﻳﻭﻥ‬

‫ﺍﻟﻣﻌﻘﺩ ‪.[Co(NH3)6]+3‬‬

‫ﻭﺍﺳﺗﻧﺎﺩﺍ ﺇﻟﻰ ﻧﻅﺭﻳﺔ ﻟﻭﺭﻱ ‪ Lowry‬ﻳﻣﻛﻥ ﻟﻶﺻﺭﺓ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ )ﻭﺑﺎﻟﺗﺎﻟﻲ ﺍﻟﻣﺭﻛﺏ ﺍﻟﻣﻌﻘﺩ ( ﺃﻥ ﺗﺗﻛﻭﻥ ﺑﻳﻥ ﺃﻱ ﺫﺭﺓ ﺃﻭ ﺃﻳﻭﻥ‬
‫ﻳﺳﺗﻁﻳﻊ ﻳﺗﻘﺑﻝ ﺯﻭﺟﺎً ﻣﻥ ﺍﻻﻟﻛﺗﺭﻭﻧﺎﺕ )‪ (acceptor‬ﻭﺍﻟﺫﻱ ﻳﻌﺩ ﺣﺎﻣﺿﺎً ﺣﺳﺏ ﻣﻔﻬﻭﻡ ﻟﻭﻳﺱ )‪،(Lewis Acid‬ﻭﺃﻳﺔ ﺫﺭﺓ ﺃﻭ‬
‫ﺃﻳﻭﻥ ﻳﺳﺗﻁﻳﻊ ﺃﻥ ﻳﻭﻓﺭ ﻫﺫﺍ ﺍﻟﺯﻭﺝ ﺍﻻﻟﻛﺗﺭﻭﻧﻲ )‪ (donor‬ﻭﺍﻟﺫﻱ ﻳﻌﺩ ﻗﺎﻋﺩﺓ ﻟﻭﻳﺱ )‪) (Lewis Base‬ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ (ﻭﻫﻲ‬
‫ﺍﻟﺟﺯﻳﺋﺎﺕ ﺃﻭ ﺍﻷﻳﻭﻧﺎﺕ ﺍﻟﺣﻳﻁﺔ ﺑﺎﻳﻭﻥ ﺍﻟﻔﻠﺯ ﺍﻟﻣﺭﻛﺯﻱ ﻭﺍﻟﺗﻲ ﻗﺩ ﺗﻣﺛﻝ ﺟﺯﻳﺋﻪ ﻣﺗﻌﺎﺩﻟﺔ ﻣﺛﻝ ‪ CO,H2O,NH3‬ﺃﻭ ﺟﺯءﺍً ﻣﻥ ﺃﻳﻭﻥ‬

‫ﻣﺛﻝ ‪. CI-, CO32-, NH2CH2COO-‬ﻭﺍﺳﺗﻧﺎﺩﺍ ﺇﻟﻰ ﺣﺎﺻﻝ ﻣﺟﻣﻭﻉ ﺍﻟﺷﺣﻧﺎﺕ ﻟﻠﻣﺭﻛﺏ ﺍﻟﻣﻌﻘﺩ ﻓﺄﻥ ﺍﻟﻣﻌﻘﺩ ﺍﻟﻧﺎﺗﺞ ﻗﺩ ﻳﻛﻭﻥ‬

‫‪ -‬ﺃﻳﻭﻧﺎً ﻣﻭﺟﺑﺎً )ﻣﻌﻘﺩ ﻛﺎﺗﻳﻭﻧﻲ ‪ (cationic complex‬ﻣﺛﻝ ‪.[Co(NH3)6]CI3‬‬

‫‪ -‬ﺃﻳﻭﻧﺎً ﺳﺎﻟﺑﺎً ) ﻣﻌﻘﺩ ﺃﻧﻳﻭﻧﻲ ‪ ( anionic complex‬ﻣﺛﻝ ]‪. K3[Cr(C2O4)3‬‬

‫‪ -‬ﻣﻌﻘﺩ ﻏﻳﺭ ﺍﻟﻛﺗﺭﻭﻟﻳﺗﻲ ﺃﻱ ﻏﻳﺭ ﻣﺷﺣﻭﻥ ) ﻳﺣﻣﻝ ﺍﻟﺷﺣﻧﺔ ﺻﻔﺭ ( ﻣﺛﻝ ]‪.[Pt(NH3)2CI2‬‬

‫ﻭﻳﻣﻛﻥ ﺗﻣﺛﻳﻝ ﺗﻔﺎﻋﻝ ﺣﻭﺍﻣﺽ ﻭ ﻗﻭﺍﻋﺩ ﻟﻭﻳﺱ ﻓﻲ ﺗﻛﻭﻳﻥ ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻟﻣﻌﻘﺩﺓ ﻛﻣﺎ ﻓﻲ ﺍﻟﺗﻔﺎﻋﻼﺕ ﺍﻟﺗﺎﻟﻳﺔ ‪-:‬‬

‫‪H‬‬ ‫‪H H+‬‬

‫‪Ag+ + N‬‬ ‫‪H‬‬ ‫‪H‬‬ ‫‪N‬‬ ‫‪Ag N‬‬ ‫‪H‬‬

‫‪Lewis acid‬‬ ‫‪H‬‬ ‫‪H‬‬
‫‪Lewis base‬‬ ‫‪H‬‬

‫‪Ion comlex‬‬

‫‪H‬‬ ‫‪H3N‬‬ ‫‪+2‬‬
‫‪N‬‬ ‫‪NH3‬‬
‫‪Cu+2‬‬ ‫‪+4‬‬ ‫‪H‬‬ ‫‪Cu‬‬
‫‪NH3‬‬
‫‪H‬‬ ‫‪H3N‬‬
‫‪Ion comlex‬‬
‫‪Lewis acid‬‬ ‫‪Lewis base‬‬

‫‪Lewis acid= metal = center of coordination.‬‬

‫‪5‬‬

‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫‪Lewis base = ligand \molecules or ions covalently bonded to metal in complex.‬‬

‫ﻭﺗﺻﻧﻑ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﻛﻘﻭﺍﻋﺩ ﻟﻭﻳﺱ ﻷﻧﻬﺎ ﺗﺷﺗﺭﻙ ﻣﻊ ﺫﺭﺍﺕ ﺍﻟﻔﻠﺯﺍﺕ ﺑﺎﻟﻣﺯﺩﻭﺟﺎﺕ ﺍﻷﻟﻛﺗﺭﻭﻧﻳﺔ ﻟﺫﻟﻙ ﺳﻭﻑ ﻧﺗﻧﺎﻭﻝ ﻣﻭﺿﻭﻉ‬
‫ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺑﺷﻲء ﻣﻥ ﺍﻟﺗﻔﺻﻳﻝ ‪.‬‬

‫‪Type of Ligands‬‬ ‫‪ -‬ﺃﻧﻭﺍﻉ ﺍﻟﻠﻳﻛــــــــﺎﻧـــــﺩﺍﺕ ‪-:‬‬

‫ﻳﻣﻛﻥ ﺗﻌﺭﻳﻑ ﺍﻟﻠﻳﻛﺎﻧﺩ ﺑﺄﻧﻪ ﺃﻱ ﺫﺭﺓ ﺃﻭ ﺃﻳﻭﻥ ﺃﻭ ﺟﺯﻱء ﻳﺳﺗﻁﻳﻊ ﺃﻥ ﻳﻠﻌﺏ ﺩﻭﺭ ﺍﻟﻣﺎﻧﺢ ﻓﻲ ﺗﻛﻭﻳﻥ ﺁﺻﺭ ﺗﻧﺎﺳﻘﻳﺔ ﻭﺍﺣﺩﺓ‬
‫ﺃﻭ ﺃﻛﺛﺭ ‪ ،‬ﻭﺗﻘﺩﻡ ﺃﻏﻠﺏ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺯﻭﺟﺎً ﺍﻟﻛﺗﺭﻭﻧﻳﺎً ﻗﺎﺑﻼً ﻟﻼﺭﺗﺑﺎﻁ ﺑﺂﺻﺭﺓ ﺳﻛﻣﺎ ﻣﻊ ﺍﻟﺫﺭﺓ ﺍﻟﻣﺭﻛﺯﻳﺔ ‪ ،‬ﻭﻫﻧﺎﻙ ﺑﻌﺽ‬
‫ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﺗﻲ ﺗﺳﺗﺧﺩﻡ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ‪ π‬ﻓﻲ ﺍﻻﺭﺗﺑﺎﻁ ﻣﺛﻝ ‪ C6H6‬ﻭ ‪ C2H4‬ﻭﺗﺳﻣﻰ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﺗﻲ ﺗﺗﺿﻣﻥ ﺫﺭﺓ ﻭﺍﺣﺩﺓ‬
‫ﻗﺎﺑﻠﺔ ﻟﻼﺭﺗﺑﺎﻁ ﻣﻊ ﺍﻟﺫﺭﺓ ﺍﻟﻣﺭﻛﺯﻳﺔ ﻟﻠﻔﻠﺯ ﺑﺎﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﺣﺎﺩﻳﺔ ﺍﻟﺳﻥ )‪ (monodentate ligands‬ﻛﻣﺎ ﻓﻲ ﺍﻷﻣﺛﻠﺔ ﺍﻟﺗﺎﻟﻳﺔ‬

‫‪-:‬‬

‫‪Monodentate Ligands‬‬

‫‪Fluoride ion Chloride ion Bromide ion Iodide ion‬‬

‫‪Hydroxide ion‬‬ ‫‪Water‬‬ ‫‪Ammonia‬‬ ‫‪Thiocynate ion‬‬
‫‪O‬‬
‫‪Carbon monoxide‬‬ ‫‪CN‬‬ ‫‪Pyridine‬‬
‫)‪(Carbonyle‬‬ ‫‪N+‬‬ ‫‪Cyanide ion‬‬

‫–‪O‬‬
‫‪Nitrate ion‬‬

‫‪ -‬ﻭﻫﻧﺎﻙ ﺍﻟﻌﺩﻳﺩ ﻣﻥ ﺍﻷﻳﻭﻧﺎﺕ ﺃﻭ ﺍﻟﺟﺯﻳﺋﺎﺕ ﺍﻟﺗﻲ ﻟﻬﺎ ﺍﻟﻘﺩﺭﺓ ﻋﻠﻰ ﺍﻷﺭﺗﺑﺎﻁ ﺑﺄﻳﻭﻥ ﺍﻟﻔﻠﺯ ﻋﺑﺭ ﺃﻛﺛﺭ ﻣﻥ ﺫﺭﺓ ﻣﺳﺎﻫﻣﺔ ﻭﺍﺣﺩﺓ‬

‫ﺃﻱ ﺃﺫﺍ ﺍﺣﺗﻭﺕ ﺍﻟﺟﺯﻳﺋﺔ ﺃﻭ ﺍﻷﻳﻭﻥ ﻋﻠﻰ ﺫﺭﺗﻳﻥ ﻗﺎﺩﺭﺗﻳﻥ ﻋﻠﻰ ﺍﻻﺭﺗﺑﺎﻁ ﺑﺄﻳﻭﻥ ﺍﻟﻔﻠﺯ ﺍﻟﻣﺭﻛﺯﻱ ﺑﺄﻧﻬﺎ ﻟﻳﻛﺎﻧﺩﺍﺕ ﺛﻧﺎﺋﻳﺔ ﺍﻟﺳﻥ‬
‫)‪ (Bidentate ligands‬ﻛﻣﺎ ﻓﻲ ﺍﻷﻣﺛﻠﺔ ﺍﻟﺗﺎﻟﻳﺔ ‪:‬‬

‫‪6‬‬

‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫‪Bidentate Ligands‬‬

‫)‪Ethylenediamine(en‬‬ ‫‪Oxalate ion‬‬ ‫‪Acetyl acetate‬‬
‫‪O‬‬
‫_‬ ‫_‬
‫‪H2N CH C OH‬‬
‫‪O‬‬ ‫‪O‬‬
‫‪ON‬‬ ‫‪OC‬‬ ‫‪H‬‬
‫)‪Glycine(gly‬‬
‫‪O‬‬ ‫‪O‬‬
‫‪Nitrate ion‬‬
‫‪Carbonate ion‬‬

‫‪ -‬ﺃﻣﺎ ﺍﻟﻣﺟﺎﻣﻳﻊ ﺍﻟﺗﻲ ﺗﺣﺗﻭﻱ ﻋﻠﻰ ﺛﻼﺛﺔ ﺃﻭ ﺃﺭﺑﻌﺔ ﻭ ﺃﺣﻳﺎﻧﺎً ﺃﻛﺛﺭ ﻣﻥ ﺫﻟﻙ ﻣﻥ ﺍﻟﺫﺭﺍﺕ ﺍﻟﻘﺎﺩﺭﺓ ﻋﻠﻰ ﺍﻟﻣﺳﺎﻫﻣﺔ ﻓﻲ ﺗﺭﺍﺑﻁ‬
‫ﺗﻧﺎﺳﻘﻲ ﺍﻟﺗﻲ ﺗﺳﻣﻰ ﺑﺎﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﻣﺗﻌﺩﺩﺓ ﺍﻟﺳﻥ )‪ ( Multidentate Ligands‬ﻭﻛﻣﺛﺎﻝ ﻋﻠﻰ ﺫﻟﻙ ﻟﻳﻛﺎﻧﺩ ﺣﺎﻣﺹ ﺍﻟﺧﻠﻳﻙ‬

‫ﺍﺛﻳﻠﻳﻥ ﺛﻧﺎﺋﻲ ﺍﻷﻣﻳﻥ )‪. (EDTA‬‬

‫‪EDTA(Ethylediamine tetraacetic acid)bounded Co+3 by six donors in [CoEDTA]-‬‬

‫ﻓﺎﻟﺫﺭﺍﺕ ﺍﻟﺳﺗﺔ ﺍﻟﻘﺎﺩﺭﺓ ﻋﻠﻰ ﺍﻻﺭﺗﺑﺎﻁ ﺍﻟﺗﻧﺎﺳﻘﻲ ﺍﻟﺗﻲ ﻳﺗﺿﻣﻧﻬﺎ ﺍﻟﻠﻳﻛﺎﻧﺩ ﺗﺭﺗﺑﻁ ﺑﺷﺩﺓ ﺑﺄﻳﻭﻧﺎﺕ ﺍﻟﻔﻠﺯﺍﺕ ‪،‬ﻟﺫﻟﻙ ﻧﺟﺩ ﺇﻥ ﻟﻬﺫﺍ‬
‫ﺍﻟﻠﻳﻛﺎﻧﺩ ﺍﺳﺗﻌﻣﺎﻻﺕ ﻛﺛﻳﺭﺓ ﻭﻣﻬﻣﺔ ﺟﺩﺍً‪.‬‬

‫‪-‬ﺃﻣﺎ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﻛﻠﻳﺗﻳﺔ )‪ (Chelating ligands‬ﻓﻬﻲ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﺗﻲ ﺗﺣﺗﻭﻱ ﻋﻠﻰ ﻣﺟﻣﻭﻋﺗﻳﻥ ﻭﻅﻳﻔﻳﺗﻳﻥ ﺃﻭﺃﻛﺛﺭ ﻗﺎﺩﺭﺓ‬
‫ﻋﻠﻰ ﻭﻫﺏ ﺯﻭﺝ ﻣﻥ ﺍﻻﻟﻛﺗﺭﻭﻧﺎﺕ ﺍﻟﺗﻲ ﻗﺩ ﺗﻬﺑﻬﺎ ﻣﺟﺎﻣﻳﻊ ﻣﺗﻧﺎﺳﻘﺔ ﻗﺎﻋﺩﻳﺔ ﻣﺛﻝ ﻣﺟﻣﻭﻋﺔ ﺍﻻﻣﻳﻥ ‪ :NH2‬ﺃﻭ ﻣﺟﻣﻭﻋﺎﺕ‬
‫ﺣﺎﻣﺿﻳﺔ ﻓﻘﺩﺕ ﺑﺭﻭﺗﻭﻧﺎﺗﻬﺎ ﻭﻧﺫﻛﺭ ﻣﻥ ﻫﺫﻩ ﺍﻟﻣﺟﺎﻣﻳﻊ )‪ ، (-COOH ,-SO3H ,-NHO‬ﺑﺣﻳﺙ ﺗﺭﺗﺑﻁ ﻓﻲ ﻣﻭﻗﻌﻳﻥ ﺃﻭ ﺃﻛﺛﺭ ﻓﻲ‬

‫‪7‬‬

‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﺁﻥ ﻭﺍﺣﺩ ﻣﻊ ﻧﻔﺱ ﺍﻷﻳﻭﻥ ﺍﻟﻔﻠﺯﻱ ﻣﻛﻭﻧﺔ ﺣﻠﻘﺔ ﺃﻭ ﺃﻛﺛﺭ ‪ ،‬ﻛﻣﺎ ﻭﺗﻌﺩ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﺛﻧﺎﺋﻳﺔ ﺍﺑﺳﻁ ﻭﺃﺷﻬﺭ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﻛﻳﻠﻳﺗﻳﺔ ﻛﻣﺎ‬
‫ﻓﻲ ﺍﻷﻣﺛﻠﺔ ﺍﻟﺗﺎﻟﻳﺔ ‪:‬‬

‫‪OC‬‬ ‫‪O‬‬ ‫‪oCO‬‬ ‫‪-2‬‬
‫‪CH2‬‬
‫‪Cu‬‬ ‫‪NH2 CH2‬‬ ‫‪OCO‬‬ ‫‪OCO‬‬

‫‪NH2‬‬ ‫‪Pt‬‬

‫‪Diglycinato copper(II) complex‬‬ ‫‪OCO‬‬ ‫‪OCO‬‬

‫‪Bis(oxalato)platinate(IV)ion‬‬

‫‪-‬ﻭﻻﺑﺩ ﻣﻥ ﺍﻻﺷﺎﺭﺓ ﺍﻟﻰ ﺑﻌﺽ ﺍﻟﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﺗﻲ ﻳﻣﻛﻥ ﺃﻥ ﺗﺷﻐﻝ ﻓﻲ ﻧﻔﺱ ﺍﻟﺗﺭﻛﻳﺏ ﻣﻭﺍﻗﻊ ﺗﻧﺎﺳﻘﻳﺔ ﻓﻲ ﺫﺭﺗﻳﻥ ﻣﺭﻛﺯﻳﺗﻳﻥ ﻭﺭﺑﻣﺎ‬
‫ﻓﻲ ﺛﻼﺙ ﺫﺭﺍﺕ ‪ ،‬ﺃﻱ ﻳﻣﻛﻧﻬﺎ ﺃﻥ ﺗﻘﻭﻡ ﺑﺩﻭﺭ ﺍﻟﺟﺳﺭ ﻟﺗﻌﻁﻲ ﻣﺭﻛﺑﺎﺕ ﻣﻌﻘﺩﺓ ﻣﺗﻌﺩﺩﺓ ﺍﻟﻣﺭﻛﺯ ‪ ،‬ﻭﻟﻳﻛﺎﻧﺩﺍﺕ ﻛﻬﺫﻩ ﺗﺳﻣﻰ ﺑﺎﻟﻠﻳﻛﺎﻧﺩﺍﺕ‬
‫ﺍﻟﺟﺳﺭﻳﺔ )‪،(Bridge ligands‬ﻭﻓﻲ ﻛﺛﻳﺭ ﻣﻥ ﺍﻟﺣﺎﻻﺕ ﻳﻛﻭﻥ ﺍﻟﻠﻳﻛﺎﻧﺩ ﺍﻟﺟﺳﺭﻱ ﺃﺣﺎﺩﻱ ﺍﻟﺳﻥ ﻣﺛﻝ ﺍﻟﻬﺎﻟﻳﺩﺍﺕ ‪ ،‬ﻭﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ‬

‫ﺍﻟﺣﺎﻭﻳﺔ ﻋﻠﻰ ﺫﺭﺓ ﻭﺍﺣﺩﺓ ﻣﺎﻧﺣﺔ ﻣﺛﻝ ‪ OH-‬ﻭ ‪ NH2-‬ﻛﻣﺎ ﻓﻲ ﺍﻷﻣﺛﻠﺔ ﺍﻟﺗﺎﻟﻳﺔ‪:‬‬

‫‪8‬‬

‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﺃﻣﺎ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﺗﻲ ﺗﺣﺗﻭﻱ ﻋﻠﻰ ﺃﻛﺛﺭ ﻣﻥ ﺫﺭﺓ ﻣﺎﻧﺣﺔ ﻓﺗﻘﻭﻡ ﻏﺎﻟﺑﺎً ﺑﺩﻭﺭ ﻟﻳﻛﺎﻧﺩﺍﺕ ﺟﺳﺭﻳﺔ ﺛﻧﺎﺋﻳﺔ ﺍﻟﺳﻥ ‪،‬ﻣﺛﻝ ﺃﻳﻭﻥ ﺍﻟﻛﺑﺭﻳﺗﺎﺕ‬
‫‪ SO4-2‬ﺍﻟﺫﻱ ﻳﻣﻛﻥ ﺃﻥ ﻳﺳﻠﻙ ﺳﻠﻭﻙ ﻣﺧﺗﻠﻑ ﻛﻣﺎ ﻓﻲ ﺍﻟﺷﻛﻝ ‪:‬‬

‫‪NH3‬‬ ‫‪N‬‬ ‫‪N‬‬
‫‪N‬‬
‫‪NH3‬‬ ‫‪o‬‬

‫‪H3N‬‬ ‫‪Co O‬‬ ‫‪O Br‬‬ ‫‪Co‬‬ ‫‪S O Br‬‬
‫‪H3N‬‬ ‫‪O‬‬
‫‪S‬‬ ‫‪o‬‬ ‫‪O‬‬

‫‪N‬‬

‫‪NH3‬‬ ‫‪O‬‬

‫‪Monodentate‬‬ ‫‪Bidentate-chelate‬‬

‫‪H‬‬
‫‪N‬‬

‫‪(NH3)4Co‬‬ ‫‪Co(NH3)4‬‬

‫‪HO‬‬ ‫‪OH‬‬ ‫‪(NO3)3‬‬

‫‪S‬‬
‫‪O‬‬

‫‪O‬‬

‫‪Bidentate-bridge‬‬

‫ﺗﺳﻣﻳﺔ ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻟﻣﻌﻘﺩﺓ‪:‬‬

‫ﺃﻥ ﻟﺟﻧﺔ ﺗﺳﻣﻳﺔ ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻟﻼﻋﺿﻭﻳﺔ ﺍﻟﺗﺎﺑﻌﺔ ﻟﻼﺗﺣﺎﺩ ﺍﻟﺩﻭﻟﻲ ﻟﻠﻛﻳﻣﻳﺎء ﺍﻟﺗﻁﺑﻳﻘﻳﺔ ﻭﺍﻟﺻﺭﻓﺔ ‪(International Union of‬‬
‫)‪) Pure and Applied Chemistry‬ﻳﻛﺗﺏ ﺑﺎﻟﺣﺭﻭﻑ ﺍﻷﻭﻟﻰ ‪ ( IUPAC‬ﺍﻋﺗﻣﺩﺕ ﻣﺟﻣﻭﻋﺔ ﻣﻥ ﺍﻟﻘﻭﺍﻋﺩ ﻟﺗﺳﻣﻳﺔ ﺍﻟﻣﺭﻛﺑﺎﺕ‬

‫ﺍﻟﻣﻌﻘﺩﺓ ﻭﻓﻳﻣﺎ ﻳﻠﻲ ﺗﻠﺧﻳﺹ ﻟﻬﺫﻩ ﺍﻟﻘﻭﺍﻋﺩ‪:‬‬

‫‪-1‬ﻳﺳﻣﻰ ﺍﻻﻳﻭﻥ ﺍﻟﻣﻭﺟﺏ ﺃﻭﻻً ﺛﻡ ﻳﺗﺑﻊ ﺑﺎﻻﻳﻭﻥ ﺍﻟﻣﻭﺟﺏ )ﺍﻟﺗﺳﻣﻳﺔ ﺍﻻﻧﻛﻠﻳﺯﻳﺔ ( ﻣﺛﻝ‬

‫‪[Cr(NH3)6](NO3)3 (hexamine chromium (III) nitrate.‬‬

‫)‪K2[PtCI6] Potassium hexachloro platinate (IV‬‬

‫‪9‬‬

‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫‪-2‬ﻓﻲ ﺗﺳﻣﻳﺔ ﺍﻟﻣﺭﻛﺏ ﺍﻟﻣﻌﻘﺩ ‪،‬ﻓﺗﺳﻣﻰ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺃﻭﻻً ﻗﺑﻝ ﺍﻟﻔﻠﺯ ﺍﻟﻣﺭﻛﺯﻱ ‪.‬‬

‫‪-3‬ﺗﺳﻣﻳﺔ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ‪:‬‬

‫• ﺗﺳﻣﻰ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﺳﺎﻟﺑﺔ ﺃﻭﻻً ﺛﻡ ﺍﻟﻣﺗﻌﺎﺩﻟﺔ ﻭﻳﻠﻳﻬﺎ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﻣﻭﺟﺑﺔ ‪.‬‬
‫• ﺗﺳﻣﻰ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﺳﺎﻟﺑﺔ ﺣﺳﺏ ﺗﺳﻠﺳﻝ ﺍﻟﺣﺭﻭﻑ ﺍﻷﺑﺟﺩﻳﺔ ﻭﻛﺫﻟﻙ ﺍﻟﺣﺎﻝ ﺑﺎﻟﻧﺳﺑﺔ ﺍﻟﻰ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﻣﺗﻌﺎﺩﻟﺔ ﻭ‬

‫ﺍﻟﻣﻭﺟﺑﺔ‬
‫• ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﺳﺎﻟﺑﺔ ﺗﻧﺗﻬﻲ ﺍﺳﻣﺎﺋﻬﺎ ﺑﺎﻟﺣﺭﻑ )ﻭ(‪.(-O) ,‬‬

‫‪Ligand‬‬ ‫‪Naming‬‬ ‫‪Ligand‬‬ ‫‪Naming‬‬
‫‪Nitrite NO2-‬‬ ‫‪nitrito‬‬ ‫‪CN-‬‬ ‫‪Cyano‬‬
‫‪Sulfate SO4-2‬‬ ‫‪Sulfato‬‬ ‫‪HS-‬‬ ‫‪Thiolo‬‬
‫‪Carbonate CO3-2‬‬ ‫‪Crbonato‬‬ ‫‪CH3O-‬‬ ‫‪Methoxo‬‬
‫‪Nitrate NO3-‬‬ ‫‪Nitrato‬‬ ‫‪F-‬‬ ‫‪Fluoro‬‬
‫‪Disulfide S2-2‬‬ ‫‪Disulfido‬‬ ‫‪CI-‬‬ ‫‪Chloro‬‬
‫‪Nitride N-3‬‬ ‫‪Nitrido‬‬ ‫‪Br-‬‬ ‫‪Bromo‬‬
‫‪Oxo‬‬ ‫‪I-‬‬ ‫‪Iodo‬‬
‫‪O-2‬‬ ‫‪Hydroxo‬‬ ‫‪O2-2‬‬ ‫‪Peroxo‬‬
‫‪OH-‬‬ ‫‪Acetato‬‬ ‫‪Thiocyanato‬‬
‫‪Acetate CH3COO-‬‬ ‫‪Thiocynate SCN-‬‬

‫• ﺃﻣﺎ ﺑﻘﻳﺔ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﻛﺄﻳﻭﻥ ﻣﻭﺟﺏ ﺃﻭ ﻣﺗﻌﺎﺩﻝ ﻓﻼ ﻳﻌﻁﻰ ﻟﻬﺎ ﺃﺳﻡ ﺧﺎﺹ ﻭ ﻓﻳﻣﺎ ﻳﻠﻲ ﺑﻌﺽ ﻫﺫﻩ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ‪:‬‬

‫‪CO Carbonyl‬‬ ‫‪OH Hydroxyl‬‬ ‫‪NH2CH2CH2NH2 Ethylene diamine‬‬
‫‪NO Nitrosyl‬‬ ‫‪NH2NH3+ Hydrazinium‬‬
‫‪(C6H5)3P Triphenyl phosphine‬‬

‫• ﻳﺷﺎﺭ ﻟﻠﻣﺎء ﺑﺻﻔﺗﻪ ﻟﻳﻛﺎﻧﺩ ﺑﻛﻠﻣﺔ ‪ aqua‬ﻭﻳﺷﺎﺭ ﻟﻸﻣﻭﻧﻳﺎ ﺑﻛﻠﻣﺔ ‪.ammine‬‬

‫• ﺗﺳﺗﻌﻣﻝ ﺃﺩﻭﺍﺕ ﺍﻟﺳﺑﻕ )ﺛﻧﺎﺋﻲ ‪ ، di‬ﺛﻼﺛﻲ ‪، tri‬ﺭﺑﺎﻋﻲ ‪، tetra‬ﺧﻣﺎﺳﻲ ‪ ، penta‬ﺳﺩﺍﺳﻲ ‪ ....، hexa‬ﺍﻟﺦ( ﻗﺑﻝ‬

‫ﺃﺳﻣﺎء ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﺑﺳﻳﻁﺔ ﻣﺛﻝ ﺑﺭﻭﻣﻭ ‪ ،‬ﻧﻳﺗﺭﻭ ﻭ ﻫﻳﺩﺭﻭﻛﺳﻭ ‪ ،‬ﻓﻲ ﺣﻳﻥ ﺗﺳﺗﺧﺩﻡ ﺍﻷﺩﻭﺍﺕ ) ‪tris ، bis‬‬
‫‪ ....tetrakis،‬ﺍﻟﺦ ( ﻗﺑﻝ ﺃﺳﻣﺎء ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﻣﻌﻘﺩﺓ ﻣﺛﻝ ﺍﺛﻳﻠﻳﻥ ﺛﻧﺎﺋﻲ ﺃﻣﻳﻥ )‪ ( en‬ﻭ ﺍﺛﻳﻠﻳﻥ ﺛﻧﺎﺋﻲ ﺃﻣﻳﻥ ﺭﺑﺎﻋﻲ‬

‫ﺣﺎﻣﺽ ﺍﻟﺧﻠﻳﻙ )‪ (EDTA‬ﻭﺧﺎﺻﺔ ﻋﻧﺩ ﺍﺣﺗﻭﺍء ﺃﺳﻣﺎء ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻷﺩﻭﺍﺕ ‪ di ,tri ,tetra‬ﻣﺛﻝ‬

‫]‪K3[AI(C2O4)3‬‬ ‫)‪Potassium trioxalato aluminate(III‬‬

‫‪[Co(en)2CL2]2SO4‬‬ ‫‪Dichloro bis (ethylene diamine)Cobalt(III)sulphate.‬‬ ‫•‬

‫ﻳﻌﺑﺭ ﻋﻥ ﺣﺎﻟﺔ ﺗﺄﻛﺳﺩ ﻟﻠﺫﺭﺓ ﺍﻟﻣﺭﻛﺯﻳﺔ ﺑﺎﻷﺭﻗﺎﻡ ﺍﻟﺭﻭﻣﺎﻧﻳﺔ ﻭﺗﺣﺻﺭ ﻣﺎﺑﻳﻥ ﻗﻭﺳﻳﻥ ﻣﺑﺎﺷﺭﺓ ﺑﻌﺩ ﺍﺳﻡ ﺍﻟﻔﻠﺯ ‪.‬‬
‫• ﻋﻧﺩﻣﺎ ﻳﻛﻭﻥ ﺍﻻﻳﻭﻥ ﺍﻟﻣﻌﻘﺩ ﺍﻳﻭﻧﺎً ﺳﺎﻟﺑﺎً ﺿﻣﻥ ﺍﻟﻛﺭﺓ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ﻓﻳﻧﺗﻬﻲ ﺍﺳﻡ ﺍﻟﻔﻠﺯ ﺍﻟﻣﺭﻛﺯﻱ ﺑﺎﻟﻣﻘﻁﻊ )‪ ، ( ate‬ﺃﻣﺎ ﻓﻲ‬

‫ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻷﻳﻭﻧﻳﺔ ﺍﻟﻣﻭﺟﺑﺔ ﺃﻭ ﺍﻟﻣﺗﻌﺎﺩﻟﺔ ﻓﻳﺑﻘﻰ ﺃﺳﻡ ﺍﻟﻔﻠﺯ ﺍﻟﻣﺭﻛﺯﻱ ﺩﻭﻥ ﺗﻐﻳﻳﺭ‬ ‫•‬

‫‪Ca2[Fe(CN)6 Calcium hexacyano ferrate(II).‬‬

‫‪[Fe(H2O)6]SO4 hexaaqua iron(II) Sulphate. [Ni(DMG)2] Bis(dimethyl glyoximato)nickel(II).‬‬
‫‪[Cu(acac)2] bis (acetyl acetanato)Copper(II).‬‬

‫• ﻟﻠﻣﺟﺎﻣﻳﻊ ﺍﻟﺟﺳﺭﻳﺔ ) ﺍﻟﺗﻲ ﺗﺭﺑﻁ ﺫﺭﺗﻲ ﻓﻠﺯ ﺃﻭ ﺃﻛﺛﺭ ( ﻳﺳﺗﺧﺩﻡ ﺍﻟﺣﺭﻑ ﺍﻷﻏﺭﻳﻘﻲ ﻣﻳﻭ ‪ - µ -‬ﻗﺑﻝ ﺃﺳﻡ ﺍﻟﺟﻣﻭﻋﺔ‬

‫ﻭﺗﻛﺭﺭ ﻛﺗﺎﺑﺔ ﻫﺫﺍ ﺍﻟﺣﺭﻑ ﻗﺑﻝ ﺍﺳﻡ ﻣﺟﻣﻭﻋﺔ ﺟﺳﺭﻳﺔ ﻣﺧﺗﻠﻔﺔ ﻳﺣﻭﻳﻬﺎ ﺍﻟﻣﺭﻛﺏ ‪.‬‬

‫‪10‬‬

‫ﺣﻮراء ﻣﻬﺪي‬.‫م‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

(NH3)4 Co H2 Co(NH3)4 (NO3)4
N
NO2

Octaammine-µ-amido-µ-nitro dicobalt(III)nitrate. .Octaaqua-µ-dihydroxo diiron(III) sulphate

‫ﻋﻧﺩﻣﺎ ﻳﻛﻭﻥ ﻟﻠﻳﻛﺎﻧﺩ ﺃﻛﺛﺭ ﻣﻥ ﺟﺎﻧﺏ ﺍﻟﻼﺭﺗﺑﺎﻁ ﻓﻠﺑﻳﺎﻥ ﺟﺎﻧﺏ ﺍﻷﺭﺗﺑﺎﻁ ﻳﻛﺗﺏ ﺭﻣﺯ ﺍﻟﻌﻧﺻﺭ ﺍﻟﻣﺭﺗﺑﻁ ﻣﺑﺎﺷﺭﺓ ﺑﻌﺩ ﺍﺳﻡ‬ •
•
.ً‫ﺍﻟﻣﺟﻣﻭﻋﺔ ﺍﻟﻣﺭﺗﺑﻁ ﻣﺑﺎﺷﺭﺓ ﺑﻌﺩ ﺍﺳﻡ ﺍﻟﻣﺟﻣﻭﻋﺔ ﻣﺛﻼ‬
•
(NH4)2[Pt(SCN)6]: ammonium hexathiocyanato-S-Platinate(IV).
(NH4)3[Cr(NCS)6 : ammonium hexathiocyanato-N-Chromate(III).

‫ ﻋﻧﺩﻣﺎ ﺗﻛﻭﻥ ﺍﻟﻣﺟﻣﻭﻋﺗﺎﻥ ﻣﺗﻘﺎﺑﻠﺔ ﻓﻲ‬trans- ‫ ﻋﻧﺩﻣﺎ ﺗﻛﻭﻥ ﺍﻟﻣﺟﻣﻭﻋﺗﺎﻥ ﻣﺗﺟﺎﻭﺭﺓ ﻭ‬cis- ‫ﺗﺳﺗﻌﻣﻝ ﺍﻷﺻﻁﻼﺣﺎﺕ‬

‫ﺣﺎﻝ ﺗﻛﻭﻥ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﺛﻣﺎﻧﻳﺔ ﺍﻟﺳﻁﻭﺡ ﻭ ﺍﻟﻣﺭﺑﻊ ﺍﻟﻣﺳﺗﻭﻱ ﺑﺷﻛﻝ ﺍﻳﺯﻭﻣﺭﺍﺕ )ﻧﻔﺱ ﻣﺟﺎﻣﻳﻊ ﺍﻟﻌﻧﺎﺻﺭ ﻟﻛﻥ ﻳﺧﺗﻠﻑ ﻓﻲ‬

. ( ‫ﺗﺭﺗﻳﺏ ﻫﺫﻩ ﺍﻟﻣﺟﺎﻣﻳﻊ ﻭﺳﻧﺗﻁﺭﻕ ﺍﻟﻰ ﺍﻳﺯﻭﻣﺭﻳﺔ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ﻓﻲ ﻣﺣﺎﺿﺭﺍﺕ ﻗﺎﺩﻣﺔ‬

NH3 NH3 +

+

H3N Br Br NH3
Rh
Rh

H3N Br H3N Br

NH3 NH3

cis-dibromotetraammine- trans-dibromotetraammine-
rhodium(III) ion rhodium(III) ion

: ‫ﺃﻣﺛﻠﺔ ﻟﺗﺳﻣﻳﺔ ﺍﻟﻣﻌﻘﺩﺍﺕ‬
[Fe(OH2)6]CI2 : hexaaqua iron (II) chloride.

K3[Co(CN)6] : Potassium hexacyano cobaltate(III) .

[PtCI2(PMe3)2] : dichloro bis (trimethyl phosphine )platinum(II)

[RhCI2(H)(PiPr3)3] : dichloro hydro tris (tri isopropyl phosphine ) rhodium(III)

K[Pt(NH3)Cl5] = potassium amminepentachloroplatinate(IV)

[Rh(NH3)5I]I2 = pentaammineiodorhodium(III) iodide.
[Fe(C2O4)3]-3 = trioxalatoferrate(III) ion.
[Co(en)2(H2O)Cl]Cl2 = aquachlorobis(ethylenediamine)cobalt(III)Chlorid.

(Coordination Number ) : ‫ ﺃﻷﻋﺩﺍﺩ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ‬

‫ ﻭﻋﺭﻑ ﻫﺫﺍ ﺍﻟﻌﺩﺩ ﺣﺳﺏ ﻧﻅﺭﻳﺔ‬، ‫ﻣﻥ ﺍﺣﺩﻯ ﻣﻳﺯﺍﺕ ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ﻫﻭ ﻋﺩﺩ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﻣﺭﺗﺑﻁﺔ ﺑﺎﻟﺫﺭﺓ ﺍﻟﻣﺭﻛﺯﻳﺔ‬

‫ﻓﺭﻧﺭ ﺑﺎﻟﺗﻛﺎﻓﺅ ﺍﻟﺛﺎﻧﻭﻱ ﻟﻠﺫﺭﺓ ﺍﻟﻣﺭﻛﺯﻳﺔ ﻭﻓﻲ ﺍﻻﺻﻁﻼﺣﺎﺕ ﺍﻟﺣﺩﻳﺛﺔ ﻳﺳﻣﻰ ﻫﺫﺍ ﺍﻟﻌﺩﺩ ﺍﻟﺗﻧﺎﺳﻘﻲ ﻭﺗﺗﺭﺍﻭﺡ ﻗﻳﻡ ﺍﻷﻋﺩﺍﺩ‬

11

‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ﻣﻥ ‪ 2‬ﺇﻟﻰ ‪ 12‬ﻭﻗﺩ ﺗﻣﺕ ﻣﻼﺣﻅﺔ ﻫﺫﻩ ﺍﻷﻋﺩﺍﺩ ﻓﻲ ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ﻭﺗﺣﺩﺩ ﻗﻳﻣﺔ ﺍﻟﻌﺩﺩ ﺍﻟﺗﻧﺎﺳﻘﻲ ﺣﺳﺏ‬
‫ﻁﺑﻳﻌﺔ ﺍﻷﻳﻭﻥ ﺍﻟﻔﻠﺯﻱ ‪ ،‬ﻭﺣﺎﻟﺔ ﺗﺄﻛﺳﺩﻩ ﻭﻓﻳﻣﺎ ﻳﻠﻲ ﺃﻛﺛﺭ ﺍﻷﻋﺩﺍﺩ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ﺷﻳﻭﻋﺎً ﻣﻊ ﺑﻌﺽ ﺍﻷﻣﺛﻠﺔ ﻟﻠﻣﻌﻘﺩﺍﺕ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ‪.‬‬

‫)‪Part (2‬‬ ‫ﺍﻟﻧﻅﺭﻳﺎﺕ ﻭﺍﻟﻔﺭﺿﻳﺎﺕ ﻓﻲ ﺗﻔﺳﻳﺭﺍﻟﻣﺭﻛﺏ ﺍﻟﺗﻧﺎﺳﻘﻲ ‪-:‬‬

‫ﻟﻘﺩ ﻛﺎﻥ ﻣﻥ ﺍﻟﺿﺭﻭﺭﻱ ﻭﺟﻭﺩ ﻧﻅﺭﻳﺔ ﻣﻧﺎﺳﺑﺔ ﻟﺗﻔﺳﻳﺭ ﻛﻝ ﺍﻟﺣﻘﺎﺋﻕ ﺍﻟﻌﻣﻠﻳﺔ ﻭﻟﻬﺫﺍ ﻓﻘﺩ ﻁﺭﺣﺕ ﻋﺩﺓ ﻓﺭﺿﻳﺎﺕ ﻭ ﻧﻅﺭﻳﺎﺕ‬
‫ﻭﺳﻭﻑ ﻧﻧﺎﻗﺵ ﺗﻠﻙ ﺍﻟﺗﻲ ﺍﺳﺗﺧﺩﻣﺕ ﺑﺷﻛﻝ ﻭﺍﺳﻊ ‪.‬‬

‫‪ ‬ﻧﻅﺭﻳﺔ ﺍﻟﺳﻠﺳﻠﺔ ‪(Chain Theory) -:‬‬

‫ﺗﺄﺛﺭ ﺍﻟﻛﻳﻣﻳﺎﺋﻳﻭﻥ ﺑﺷﻛﻝ ﻭﺍﺿﺢ ﺑﻣﻔﻬﻭﻡ ﻭﺟﻭﺩ ﺃﺭﺑﻌﺔ ﺃﻭﺍﺻﺭ ﻟﻠﻛﺭﺑﻭﻥ ﻭﺗﻛﻭﻳﻥ ﺍﻟﺳﻼﺳﻝ ﻛﺭﺑﻭﻥ – ﻛﺭﺑﻭﻥ ﻓﻲ ﺍﻟﻣﺭﻛﺑﺎﺕ‬
‫ﺍﻟﻌﺿﻭﻳﺔ ﻟﺫﻟﻙ ُﻗﺩﻣﺕ ﻫﺫﻩ ﺍﻟﻧﻅﺭﻳﺔ ﻓﻲ ﺗﻔﺳﻳﺭ ﻭﺟﻭﺩ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﻔﻠﺯﻳﺔ ‪ ،‬ﻭﻧﻅﺭﺍً ﻟﻼﻋﺗﻘﺎﺩ ﺍﻟﺳﺎﺋﺩ ﻓﻲ ﺫﻟﻙ ﺍﻟﻭﻗﺕ ﻋﻥ ﻭﺟﻭﺩ‬
‫ﻧﻭﻉ ﻭﺍﺣﺩ ﻣﻥ ﺍﻟﺗﻛﺎﻓﺅ ﻓﻠﻘﺩ ﺃﻗﺗﺭﺡ ﺑﻠﻭﻣﺳﺗﺭﺍﻧﺩ ﻭ ﻳﻭﺭﺟﻧﺳﻥ ﻭﺟﻭﺩ ﺛﻼﺙ ﺃﻭﺍﺻﺭ ﻟﻠﻛﻭﺑﻠﺕ ﺍﻟﺛﻼﺛﻲ )‪ Co(III‬ﻓﻲ ﻣﻌﻘﺩﺍﺗﻪ‬

‫ﺑﺎﺳﺗﺧﺩﺍﻡ ﺍﻟﺑﻧﻳﺔ ﺍﻟﺗﺳﻠﺳﻠﻳﺔ )‪ (Chain St.‬ﻓﻲ ﺗﻔﺳﻳﺭ ﻭﺟﻭﺩ ﺟﺯﻳﺋﺎﺕ ﺍﻷﻣﻭﻧﻳﺎ ﺍﻟﺳﺕ ‪ CoCI3.6NH3‬ﻛﻣﺎ ﻣﺑﻳﻥ ﺃﺩﻧﺎﻩ ‪:‬‬

‫‪Compound‬‬ ‫‪Chain Structure‬‬ ‫‪Number of CI-‬‬
‫‪CoCI3.6NH3‬‬ ‫‪precipices ions‬‬

‫‪3‬‬

‫‪12‬‬

‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫‪CoCI3.5NH3‬‬ ‫‪CI‬‬ ‫‪2‬‬
‫‪CoCI3.4NH3‬‬ ‫‪1‬‬
‫‪Co‬‬ ‫‪NH3_NH3_NH3_NH3_CI‬‬

‫‪NH3 _ CI‬‬

‫‪CoCI3.3NH3‬‬ ‫‪CI‬‬ ‫‪0‬‬

‫‪Co‬‬ ‫‪NH3_ NH3 _NH3_CI‬‬

‫‪CI‬‬

‫ﻓﻠﻘﺩ ﻭﺟﺩ ﺃﻥ ﺃﻳﻭﻧﺎﺕ ﺍﻟﻛﻠﻭﺭﻳﺩ ‪ CI-‬ﺍﻟﻐﻳﺭ ﻣﺗﺻﻠﺔ ﺍﺗﺻﺎﻻ ﻣﺑﺎﺷﺭﺍ ﺑﺎﻟﺫﺭﺓ ﺍﻟﻣﺭﻛﺯﻳﺔ ﺗﺗﺭﺳﺏ ﺑﺷﻛﻝ ‪ AgCI‬ﻋﻧﺩ ﺇﺿﺎﻓﺔ ﺯﻳﺎﺩﺓ‬
‫ﻣﻥ ﻣﺣﻠﻭﻝ ﻧﺗﺭﺍﺕ ﺍﻟﻔﺿﺔ ‪ AgNO3‬ﺑﺣﻳﺙ ﺗﺗﺧﺫ ﺍﻟﺻﻳﻎ ﺍﻟﻣﺑﻳﻧﺔ ﺃﻋﻼﻩ ‪ ،‬ﻭﻳﻣﻛﻥ ﺃﻥ ﻧﺗﻭﻗﻊ ﺑﺄﻥ ﺳﻠﻭﻙ ﺃﻳﻭﻧﺎﺕ ﺍﻟﻛﻠﻭﺭﻳﺩ ﻓﻲ‬
‫‪ CoCI3.3NH3‬ﺗﻛﻭﻥ ﻣﺷﺎﺑﻬﺔ ﻟﺗﻠﻙ ﺍﻟﺗﻲ ﻓﻲ ﺍﻟﻣﺭﻛﺏ ‪ CoCI3.4NH3‬ﻟﻛﻧﻪ ﻭﺟﺩ ﻋﻣﻠﻳﺎً ﺑﺄﻧﻪ ﻻ ﻳﻌﻁﻲ ﺭﺍﺳﺑﺎً ﻋﻧﺩ ﺇﺿﺎﻓﺔ ﻣﺣﻠﻭﻝ‬

‫ﻧﺗﺭﺍﺕ ﺍﻟﻔﺿﺔ ﻭﻫﺫﺍ ﻳﺑﻳﻥ ﺿﻌﻑ ﻧﻅﺭﻳﺔ ﺍﻟﺳﻠﺳﻠﺔ ﺣﻳﺙ ﺃﻧﻬﺎ ﻟﻡ ﺗﺳﺗﻁﻊ ﺍﻥ ﺗﻔﺳﺭ ﻛﺎﻓﺔ ﺍﻟﻧﺗﺎﺋﺞ ﺍﻟﻌﻣﻠﻳﺔ ‪.‬‬

‫‪ ‬ﻧﻅﺭﻳﺔ ﻓﺭﻧﺭ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ‪(Werner`s Coordination Theory) :‬‬
‫ﻫﺫﻩ ﺍﻟﻧﻅﺭﻳﺔ ﺃﻋﻁﺕ ﺗﻔﺳﻳﺭﺍً ﻣﻧﺎﺳﺑﺎً ﻟﻭﺟﻭﺩ ﻭﺳﻠﻭﻙ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﻔﻠﺯﻳﺔ ﺣﻳﺙ ﺗﻌﺗﺑﺭ ﺇﺣﺩﻯ ﺍﻟﻘﻭﺍﻋﺩ ﺍﻷﺳﺎﺳﻳﺔ ﺍﻟﻣﺅﺩﻳﺔ‬

‫ﺇﻟﻰ ﻣﻌﺭﻓﺔ ﺍﻟﻛﻳﻣﻳﺎء ﺍﻟﻼﻋﺿﻭﻳﺔ ﻭﻣﻔﻬﻭﻡ ﺍﻟﺗﻛﺎﻓﺅ ﺑﺎﻓﺗﺭﺍﺽ ‪:‬‬
‫‪ -1‬ﻛﻝ ﻓﻠﺯ ﻳﻣﺗﻠﻙ ﻧﻭﻋﻳﻥ ﻣﻥ ﺍﻟﺗﻛﺎﻓﺅ ‪،‬ﺗﻛﺎﻓﺅ ﺃﻭﻟﻲ ﻣﺗﺄﻳﻥ ﻭﺍﻟﺫﻱ ﻳﻌﺭﻑ ﺑﺣﺎﻟﺔ ﺍﻟﺗﺄﻛﺳﺩ )‪ (Oxidation state‬ﻭ ﺗﻛﺎﻓﺅ‬

‫ﺛﺎﻧﻭﻱ ﻏﻳﺭ ﻣﺗﺄﻳﻥ ﻭﻳﻌﺭﻑ ﺑﺎﻟﻌﺩﺩ ﺍﻟﺗﻧﺎﺳﻘﻲ )‪.(Coordination number‬‬
‫‪ -2‬ﻳﺣﺎﻭﻝ ﺇﺷﺑﺎﻉ ﺍﻟﺗﻛﺎﻓﺅ ﺍﻷﻭﻟﻲ ﻭ ﺍﻟﺗﻛﺎﻓﺅ ﺍﻟﺛﺎﻧﻭﻱ ﻛﻝ ﻋﻧﺻﺭ‪.‬‬

‫‪ -3‬ﺗﺗﺟﻪ ﺍﻟﺗﻛﺎﻓﺅﺍﺕ ﺍﻟﺛﺎﻧﻭﻳﺔ ﻧﺣﻭ ﻣﻭﺍﻗﻊ ﺛﺎﺑﺗﺔ ﻓﻲ ﺍﻟﻔﺭﺍﻍ ﺣﻭﻝ ﺃﻳﻭﻥ ﺍﻟﻔﻠﺯ ﺍﻟﻣﺭﻛﺯﻱ ‪.‬‬

‫ﻭﺑﺎﻻﻋﺗﻣﺎﺩ ﻋﻠﻰ ﻧﺗﺎﺋﺞ ﺍﻟﺩﺭﺍﺳﺎﺕ ﺍﻟﻌﻣﻠﻳﺔ ﺍﻟﻣﺑﻳﻧﺔ ﻓﻲ ﺃﺩﻧﺎﻩ ‪ ،‬ﻳﻣﻛﻥ ﺗﻭﺿﻳﺢ ﻧﻅﺭﻳﺔ ﻓﺭﻧﺭ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ‪:‬‬

‫‪13‬‬

‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﻓﺎﻟﻣﺭﻛﺏ ﺍﻷﻭﻝ ﻫﻭ ‪ [Co(NH3)6]CI3‬ﻗﺩ ﺍﺷﺑﻊ ﺗﻛﺎﻓﺅﻩ ﺍﻷﻭﻟﻲ )‪ (OX.St‬ﻟﻠﻛﻭﺑﻠﺕ)‪ Co(III‬ﺑﺛﻼﺛﺔ ﻣﻥ ﺃﻳﻭﻧﺎﺕ ﺍﻟﻛﻠﻭﺭﻳﺩ ﺍﻟﺳﺎﻟﺑﺔ‬
‫ﺍﻟﺗﻲ ﺗﻌﺎﺩﻝ ﺷﺣﻧﺔ ﺃﻳﻭﻥ ﺍﻟﻔﻠﺯ ﺍﻟﻣﺭﻛﺯﻱ ‪ ،‬ﺃﻣﺎ ﺍﻟﺗﻛﺎﻓﺅ ﺍﻟﺛﺎﻧﻭﻱ )‪ (Coordination N.‬ﻟﻠﻛﻭﺑﻠﺕ ﻫﻭ )‪ (6‬ﺍﻟﺫﻱ ﺍﺷﺑﻊ ﺑﺟﺯﻳﺋﺎﺕ‬
‫ﺍﻻﻣﻭﻧﻳﺎ ﺍﻟﻣﺗﻌﺎﺩﻟﺔ ) ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ( ﺍﻟﻣﺗﺻﻠﺔ ﻣﺑﺎﺷﺭﺓ ﺑﺫﺭﺓ ﺍﻟﻔﻠﺯ ﻭ ﻳﻘﺎﻝ ﺃﻧﻬﺎ ﻣﻭﺟﻭﺩﺓ ﻓﻲ ﺍﻟﻛﺭﺓ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ‪(Coordination‬‬

‫)‪ Sphere‬ﻟﻠﻔﻠﺯ‪.‬ﻭﺍﻟﺻﻳﻎ ﺍﻟﺑﻧﺎﺋﻳﺔ ﺍﻟﺗﻲ ﺍﻗﺗﺭﺣﻬﺎ ﻓﺭﻧﺭ ﻟﻠﻣﻌﻘﺩﺍﺕ ﻳﻣﻛﻥ ﺗﻭﺿﻳﺣﻬﺎ ﻛﻣﺎ ﻳﺄﺗﻲ ‪:‬‬

‫‪Complex Ox.St Co.N‬‬ ‫‪Structure Formula‬‬ ‫‪N.Ions in Solution‬‬ ‫‪Condictivity‬‬
‫‪[Co(NH3)6]+3 + 3CI-‬‬ ‫‪432‬‬
‫‪[Co(NH3)6]CI3 3‬‬ ‫‪6‬‬ ‫‪NH3‬‬ ‫‪Cl‬‬

‫‪H3N‬‬ ‫‪NH3‬‬
‫‪Co‬‬
‫‪Cl‬‬
‫‪NH3‬‬
‫‪H3N‬‬
‫‪NH3‬‬
‫‪Cl‬‬

‫‪CoCI3.5NH3 3‬‬ ‫‪6 Cl‬‬ ‫‪[Co(NH3)5CI]+2 + 2CI-‬‬ ‫‪261‬‬

‫‪H3N‬‬ ‫‪Co‬‬ ‫‪NH3‬‬
‫‪NH3‬‬ ‫‪NH3‬‬
‫‪Cl‬‬
‫‪CoCI3.4NH3 3‬‬ ‫‪Cl‬‬ ‫‪[Co(NH3)4CI2]+1 + CI-‬‬ ‫‪97‬‬
‫‪H3N‬‬
‫‪Cl‬‬
‫‪6‬‬

‫‪H3N‬‬ ‫‪NH3‬‬
‫‪Co‬‬
‫‪Cl‬‬

‫‪H3N‬‬ ‫‪NH3 Cl‬‬

‫‪CoCI3.3NH3 3‬‬ ‫‪6 Cl‬‬ ‫]‪[Co(NH3)3CI3‬‬ ‫‪0‬‬

‫‪H3N‬‬ ‫‪NH3‬‬
‫‪Co‬‬

‫‪Cl NH3 Cl‬‬

‫ﻭﺣﺳﺏ ﻧﻅﺭﻳﺔ ﻓﺭﻧﺭ ﺍﻟﻣﻌﻘﺩ ﺍﻷﺧﻳﺭ ﻻ ﻳﻌﻁﻲ ﺃﻳﻭﻥ ﺍﻟﻛﻠﻭﺭﻳﺩ ﻓﻲ ﺍﻟﻣﺣﻠﻭﻝ ﻭ ﺍﻟﻧﺗﺎﺋﺞ ﺍﻟﻌﻣﻠﻳﺔ ﺗﺛﺑﺕ ﺍﻥ ﺍﻟﻣﺭﻛﺑﺎﺕ ﻣﻥ ﺍﻟﻧﻭﻉ‬
‫]‪ [M+3(NH3)3CI3‬ﻻ ﺗﺗﺎﻳﻥ ﻓﻲ ﺍﻟﻣﺣﻠﻭﻝ ﻭﻫﺫﻩ ﺍﻟﺣﻘﻳﻘﺔ ﺗﺛﺑﺕ ﺧﻁﺄ ﻧﻅﺭﻳﺔ ﺍﻟﺳﻠﺳﻠﺔ ﻭ ﺗﺅﻛﺩ ﺍﻟﻧﻅﺭﻳﺔ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ‪.‬‬

‫ﻧﻅﺭﻳﺎﺕ ﺍﻟﺗﺂﺻﺭ ﻟﻠﻣﺭﻛﺑﺎﺕ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ‪Bonding Theories For Coordination Compounds‬‬

‫‪ ‬ﻧﻅﺭﻳﺔ ﺁﺻﺭﺓ ﺍﻟﺗﻛﺎﻓﺅ )‪Valence Bond Theory -: ( V.B.T‬‬

‫‪14‬‬

‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﻟﻘﺩ ﺗﻡ ﺗﻁﻭﻳﺭ ﻛﺛﻳﺭ ﻣﻥ ﺍﻟﻣﻔﺎﻫﻳﻡ ﺍﻟﺣﺩﻳﺛﺔ ﻟﻧﻅﺭﻳﺔ ﺁﺻﺭﺓ ﺍﻟﺗﻛﺎﻓﺅ ﻭ ﺗﻁﺑﻳﻘﺎﺗﻬﺎ ﻋﻠﻰ ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ﻣﻥ ﻗﺑﻝ‬

‫ﺑﺎﻭﻟﻧﻙ ﻭﻫﻲ ﺫﺍﺕ ﻋﻼﻗﺔ ﻭﺛﻳﻘﺔ ﺑﺎﻟﺗﻬﺟﻳﻥ ﻭ ﺍﻟﺷﻛﻝ ﺍﻟﻬﻧﺩﺳﻲ ﻭﺑﻣﻭﺟﺏ ﻫﺫﻩ ﺍﻟﻧﻅﺭﻳﺔ ﺗﻡ ﺗﻔﺳﻳﺭ ﺍﻟﺑﻧﻳﺎﺕ ﻭ ﺍﻟﺧﻭﺍﺹ‬

‫ﺍﻟﻣﻐﻧﺎﻁﻳﺳﻳﺔ ﻟﻠﻣﺭﻛﺑﺎﺕ ﺍﻟﻣﻌﻘﺩﺓ ﺣﻳﺙ ﺗﻔﺳﺭ ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ﺑﺄﻧﻬﺎ ﺗﻧﺗﺞ ﻣﻥ ﺗﺩﺍﺧﻝ ﺃﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﻠﻳﻛﺎﻧﺩ‬
‫ﺍﻟﻣﻣﺗﻠﺋﺔ )‪ (occupied orbital‬ﻭﺃﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﻔﻠﺯ ﺍﻟﺷﺎﻏﺭﺓ )‪ (vacant orbital‬ﻟﻐﺭﺽ ﺗﻛﻭﻳﻥ ﺃﻭﺍﺻﺭ ﺗﺳﺎﻫﻣﻳﺔ‬

‫ﺗﻧﺎﺳﻘﻳﺔ )‪.(Coordinate Covalent Bonds‬‬

‫‪M L ML‬‬

‫‪Vacant metal‬‬ ‫‪Occupied ligand‬‬ ‫‪Coordinate covalent‬‬
‫‪bond‬‬

‫ﻭﺗﺣﺩﺩ ﺍﻋﺩﺍﺩ ﺍﻟﺗﻧﺎﺳﻕ ﻭﺍﻟﺑﻧﻰ ﺍﻟﻬﻧﺩﺳﻳﺔ ﺑﺷﻛﻝ ﻛﺑﻳﺭ ﺑﻭﺍﺳﻁﺔ ﺍﻷﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﺟﺎﻫﺯﺓ ﻟﻠﺗﺂﺻﺭ ‪،‬ﺍﻷﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﻬﺟﻳﻧﺔ‬
‫ﺍﻟﺷﺎﺋﻌﺔ ﺍﻟﺗﻲ ﻧﺗﻌﺎﻣﻝ ﻣﻌﻬﺎ ﻓﻲ ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ﻣﺑﻳﻧﺔ ﻓﻲ ﺍﻟﺟﺩﻭﻝ ﺍﻟﺗﺎﻟﻲ ‪:‬‬

‫‪Coordinatio‬‬ ‫‪Type of Hybridisation‬‬ ‫‪Distribution of hybrid‬‬ ‫‪Examples‬‬
‫‪n Number‬‬ ‫‪orbitals in space‬‬
‫‪Sp‬‬ ‫‪[Ag(NH3)2]+‬‬
‫‪2‬‬

‫‪4 sp3‬‬ ‫‪[CoCI4],[Ni(CO)4],‬‬
‫‪[Zn(NH3)4]+2‬‬

‫‪4 dsp2‬‬ ‫‪[Ni(CN)4]-2‬‬
‫‪,[Pt(NH3)4]+2‬‬

‫‪5‬‬ ‫‪sp3d‬‬ ‫‪Trigonal bipyramidal‬‬ ‫‪[TaF5] ,[CuCI5]-3‬‬

‫‪6‬‬ ‫‪32‬‬ ‫‪Octahedral‬‬ ‫‪[Co(NH3)6]+3 ,[PtCI6]-2‬‬
‫‪,[Cr(H2O)6]+3‬‬
‫‪sp d (nd orbitals are‬‬

‫‪involved – outer orbital‬‬

‫‪complex or high spin or‬‬

‫)‪spin free complex‬‬

‫‪6 d2sp3((n-1) d orbitals are‬‬ ‫‪Octahedral‬‬ ‫‪[Co(CN)6]-3‬‬
‫‪involved –inner orbital or‬‬
‫‪low spin or spin paired‬‬
‫)‪complex‬‬

‫‪15‬‬

‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﻭﻳﻌﺩ ﺗﻛﻭﻳﻥ ﺍﻟﻣﻌﻘﺩ ﻣﻥ ﻭﺟﻬﺔ ﻧﻅﺭ ﺁﺻﺭﺓ ﺍﻟﺗﻛﺎﻓﺅ ﺗﻔﺎﻋﻼ ً◌ﺑﻳﻥ ﻗﺎﻋﺩﺓ ﻟﻭﻳﺱ ) ﻟﻳﻛﺎﻧﺩ ( ﻭ ﺣﺎﻣﺽ ﻟﻭﻳﺱ ) ﻓﻠﺯ ﺍﻭ ﺍﻳﻭﻥ ﻓﻠﺯ (‬
‫ﻣﻊ ﺗﻛﻭﻳﻥ ﺁﺻﺭﺓ ﺗﺳﺎﻫﻣﻳﺔ ﺗﻧﺎﺳﻘﻳﺔ ﻭﻳﻣﻛﻥ ﺗﻣﺛﻳﻝ ﺃﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﻔﻠﺯ ﺑﺷﻛﻝ ﻣﺭﺑﻌﺎﺕ ﺃﻭ ﺩﻭﺍﺋﺭ ﻟﺑﻳﺎﻥ ﺗﻭﺯﻳﻊ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ﺍﻟﻔﻠﺯ ﻭ‬

‫ﺍﻟﻠﻳﻛﺎﻧﺩ ‪ ،‬ﻭﻳﻌﺩ ﺍﺳﻠﻭﺏ ﺗﻁﺑﻳﻕ ﺁﺻﺭﺓ ﺍﻟﺗﻛﺎﻓﺅ ﻧﺎﺟﺣﺎً ﻋﻠﻰ ﻛﺛﻳﺭ ﻣﻥ ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ﻭﻓﻳﻣﺎ ﻳﻠﻲ ﻧﻭﺿﺢ ﺗﻁﺑﻳﻕ ﻫﺫﻩ ﺍﻟﻧﻅﺭﻳﺔ‬
‫ﻋﻠﻰ ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ﻭﺑﺈﺷﻛﺎﻟﻬﺎ ﺍﻟﻬﻧﺩﺳﻳﺔ ﺍﻟﻣﻭﺿﺣﺔ ﻓﻲ ﺍﻟﺟﺩﻭﻝ ﺍﻋﻼﻩ ‪:‬‬

‫ﺍﻟﻣﻌﻘﺩﺍﺕ ﺫﺍﺕ ﺍﻟﺷﻛﻝ ﺍﻟﻬﻧﺩﺳﻲ ﺭﺑﺎﻋﻲ ﺍﻟﺳﻁﻭﺡ )‪(Tetrahedral‬ﺗﻬﺟﻳﻥ )‪:(sp3‬‬ ‫ﺍﻟﻌ•ﺩﺩ ﺍﻟﺗﻧﺎﺳﻘﻲ ‪4‬‬

‫ﺍﻳﻭﻥ‪ Co(II‬ﻳﻣﺗﻠﻙ ﺳﺑﻌﺔ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ‪ d‬ﻭﻧﺗﻭﻗﻊ ﻭﺟﻭﺩ ﺛﻼﺙ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ﻣﻧﻔﺭﺩﺓ ﻓﻲ ﺍﻻﻳﻭﻥ ﺍﻟﺣﺭ ‪،‬ﻭﺑﺫﻟﻙ ﻓﺎﻻﻭﺭﺑﻳﺗﺎﻻﺕ‬
‫ﺍﻟﺟﺎﻫﺯﺓ ﻟﻠﺗﺂﺻﺭ ﻫﻲ ﺍﻭﺭﺑﻳﺗﺎﻝ ‪ 4s‬ﻭﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ 4p‬ﺍﻟﺛﻼﺛﺔ ‪ ،‬ﻭﻫﺫﻩ ﺍﻻﻭﺭﺑﻳﺗﺎﻻﺕ ﻣﺳﺗﻌﺩﺓ ﻻﺳﺗﻘﺑﺎﻝ ﺃﺯﻭﺍﺝ ﺍﻻﻟﻛﺗﺭﻭﻧﺎﺕ ﺍﻟﺗﻲ‬
‫ﺗ ﺍﻬﻟﺑﻌﺩﻬﺩﺎ ﺍﺃﻟﺗﺭﻧﺑﺎﻌﺳﺔﻘﻲﻟﻳ)ﻛﺎ‪4‬ﻧ(ﺩ‪:‬ﺍﺕ ﻣﻛﻭﻧﺔ ﻣﻌﻘﺩﺍً ﺭﺑﺎﻋﻲ ﺍﻟﺳﻁﻭﺡ ﺃﻭﺍﺻﺭﻩ ﺍﻟﻬﺟﻳﻧﺔ ﻣﻥ ﻧﻭﻉ ‪ sp3‬ﻛﻣﺎ ﻓﻲ ﺍﻟﻣﻌﻘﺩ ‪ [CoCI4]2-‬ﺍﻟﺫﻱ ﻳﻛﻭﻥ‬
‫ﺫﺍ ﺧﻭﺍﺹ ﺑﺎﺭﺍﻣﻐﻧﺎﻁﻳﺳﻳﺔ ﺑﺳﺑﺏ ﺍﺣﺗﻭﺍﺋﻪ ﻋﻠﻰ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ﻣﻧﻔﺭﺩﺓ ‪ ،‬ﻭﻳﻣﻛﻥ ﺗﻣﺛﻳﻠﻪ ﺣﺳﺏ ﻧﻅﺭﻳﺔ )‪ (V.B.T‬ﻛﻣﺎ ﻓﻲ ﺍﻟﺷﻛﻝ‬

‫ﺃﺩﻧﺎﻩ ‪،‬ﻭﻣﻥ ﺍﻷﻣﺛﻠﺔ ﻋﻠﻰ ﻫﻛﺫﺍ ﻣﻌﻘﺩﺍﺕ )ﻣﻌﻘﺩ )‪ [NiCI4]2-(d8‬ﻭﻣﻌﻘﺩ )‪.( [Zn(OH)4]2- (d10‬‬

‫‪Ni+2:‬‬

‫‪[NiCI4]-2‬‬

‫ﻭﻧﻼﺣﻅ ﺃﻥ ﺍﻳﻭﻥ )‪ Zn(II‬ﻳﻣﺗﻠﻙ ﻋﺷﺭﺓ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ‪ ، d‬ﻭﻟﻬﺫﺍ ﺍﻟﺳﺑﺏ ﻻ ﺗﻛﻭﻥ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ 3d‬ﺟﺎﻫﺯﺓ ﻹﻏﺭﺍﺽ ﺍﻟﺗﺂﺻﺭ ‪،‬‬
‫ﻭﺑﺫﻟﻙ ﺗﺳﺗﻌﻣﻝ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ 4s‬ﻭ ‪ 4p‬ﻟﺗﻛﻭﻳﻥ ﻣﻌﻘﺩﺍﺕ ﺭﺑﺎﻋﻳﺔ ﺍﻟﺳﻁﻭﺡ ﻛﻣﺎ ﻓﻲ ﻣﻌﻘﺩﺍﺕ ‪ [ZnCI4]-2‬ﻭ ‪. [Zn(OH)4]-2‬‬

‫‪16‬‬

‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﻣﻌﻘﺩﺍﺕ ﺗﻧﺎﺳﻘﻳﺔ ﺫﺍﺕ ﺍﻟﺷﻛﻝ ﺍﻟﻬﻧﺩﺳﻲ ﻣﺭﺑﻊ ﻣﺳﺗﻭﻱ )‪(Squre planer‬ﺗﻬﺟﻳﻥ )‪:(dsp2‬‬

‫ﺗﻣﺗﻠﻙ ﺍﻳﻭﻧﺎﺕ )‪ Ni(II),pd(II),Pt(II‬ﺗﺭﻛﻳﺑﺎً ﺍﻟﻛﺗﺭﻭﻧﻳﺎً ‪ d8‬ﺗﺅﻫﻠﻬﺎ ﻟﺗﻛﻭﻳﻥ ﻣﻌﻘﺩﺍﺕ ﺭﺑﺎﻋﻳﺔ ﻣﺳﺗﻭﻳﺔ ‪ dsp2‬ﺫﺍﺕ ﺧﺻﺎﺋﺹ‬
‫ﺩﺍﻳﺎﻣﻐﻧﺎﻁﻳﺳﻳﺔ ﻭﺗﻌﺩ ﺍﻟﺑﻧﻳﺔ ﺍﻷﻛﺛﺭ ﺷﻳﻭﻋﺎً ﻟﻬﻛﺫﺍ ﺍﻳﻭﻧﺎﺕ ﺣﻳﺙ ﻻ ﺗﺣﺗﻭﻱ ﻋﻠﻰ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ﻣﻧﻔﺭﺩﺓ ﻭﻳﻣﻛﻥ ﺗﻣﺛﻳﻝ ﺍﻟﺗﺭﺗﻳﺏ‬

‫ﺍﻻﻟﻛﺗﺭﻭﻧﻲ ﻟﻬﺫﻩ ﺍﻻﻳﻭﻧﺎﺕ ﻓﻲ ﻣﻌﻘﺩﺍﺗﻬﺎ ﻛﻣﺎ ﻓﻲ ﺃﺩﻧﺎﻩ‪:‬‬

‫‪Pt+2 = [Xe] 4 f14‬‬ ‫‪5d8‬‬ ‫‪6s0‬‬ ‫‪6p0‬‬
‫‪[PtCI4]-2 = [Xe] 4 f14‬‬ ‫‪5d8‬‬ ‫‪6s‬‬ ‫‪6p‬‬

‫‪CI-‬‬
‫‪four dsp2 bonds to the ligands‬‬

‫ﻭﻧﻼﺣﻅ ﺍﻥ ‪ d8‬ﻻﻳﻭﻥ )‪ Ni(II‬ﺃﻳﺿﺎ ﻳﻛﻭﻥ ﻣﻌﻘﺩﺍﺕ ﺭﺑﺎﻋﻳﺔ ﺍﻟﺳﻁﻭﺡ ‪ sp3‬ﺫﺍﺕ ﺧﺻﺎﺋﺹ ﺑﺎﺭﺍﻣﻐﻧﺎﻁﻳﺳﻳﺔ ﻛﻣﺎ ﺑﻳﻧﺎ ﺳﺎﺑﻘﺎً‬
‫ﻟﻣﻌﻘﺩ ‪ [NiCI4]-2‬ﻭ ﻣﻌﻘﺩ ‪ ، [Ni(NH3)4]+2‬ﻭﻣﻥ ﺍﻟﻣﻌﺭﻭﻑ ﺑﺻﻭﺭﺓ ﻭﺻﻔﻳﺔ ﺇﻥ ﺍﻟﺗﺭﻛﻳﺏ ﺍﻻﻟﻛﺗﺭﻭﻧﻲ ﻟﻠﻔﻠﺯ ﻳﻔﺿﻝ ﺑﻧﻳﺔ‬
‫ﻫﻧﺩﺳﻳﺔ ﻣﻌﻳﻧﺔ ﻋﻠﻰ ﺑﻧﻳﺔ ﻫﻧﺩﺳﻳﺔ ﺃﺧﺭﻯ ‪.‬ﻓﻌﻧﺩﻣﺎ ﺗﻛﻭﻥ ﺫﺭﺓ ﺍﻟﻔﻠﺯ ﺍﻻﻧﺗﻘﺎﻟﻲ ﻣﻌﻘﺩﺍً ﺗﺳﺎﻫﻣﻳﺎً ﻓﻬﻲ ﺗﻣﻳﻝ ﻷﻥ ﺗﻔﺿﻝ ﺇﺣﺩﻯ ﺍﻟﺑﻧﻲ‬
‫ﺍﻟﻬﻧﺩﺳﻳﺔ ﺍﻟﺗﻲ ﺗﺅﻣﻥ ﻟﻬﺎ ﺍﻗﻝ ﻋﺩﺩ ﻣﻣﻛﻥ ﻣﻥ ﺍﻻﻟﻛﺗﺭﻭﻧﺎﺕ ﺍﻟﻣﻧﻔﺭﺩﺓ ‪.‬ﻭ ﺗﻌﺩ ﺑﻧﻳﺔ ﺍﻟﻣﺭﺑﻊ ﺍﻟﻣﺳﺗﻭﻱ ﺍﻷﻛﺛﺭ ﺷﻳﻭﻋﺎً ﻻﻳﻭﻧﺎﺕ )‪(d8‬‬

‫)‪ Pt(II)، Pd(II)،Ni(II‬ﻭ )‪ Au(III‬ﺣﻳﺙ ﻻ ﺗﺣﺗﻭﻱ ﻋﻠﻰ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ﻣﻧﻔﺭﺩﺓ ‪.‬‬

‫ﻛﻣﺎ ﺗﺷﺗﻬﺭ ﺑﻌﺽ ﺍﻻﻳﻭﻧﺎﺕ ﻣﺛﻝ )‪، Ag(II) ، Cu(II) (d9‬ﻭ )‪، Co(II) (d7‬ﺑﺗﻛﻭﻳﻥ ﻫﺫﺍ ﺍﻟﻧﻭﻉ ﻣﻥ ﺍﻟﻣﻌﻘﺩﺍﺕ ﻭﻫﻲ ﺗﺣﺗﻭﻱ‬
‫ﻋﻠﻰ ﺇﻟﻛﺗﺭﻭﻥ ﻣﻧﻔﺭﺩ ﻭﺍﺣﺩ ﻓﻘﻁ ‪،‬ﺃﻱ ﺃﻧﻬﺎ ﺗﻛﻭﻥ ﺫﺍﺕ ﺧﺻﺎﺋﺹ ﻣﻐﻧﺎﻁﺑﺳﺑﺔ ﻣﺧﺗﻠﻔﺔ ﻋﻥ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻷﺧﺭﻯ ﺍﻟﻣﺷﺎﺑﻬﺔ ﻟﻬﺎ ﻓﻲ‬

‫ﺍﻟﺗﻬﺟﻳﻥ ﻭﺍﻟﺷﻛﻝ ﺍﻟﻬﻧﺩﺳﻲ‪.‬‬

‫]‪Cu+2 = [Ar‬‬ ‫‪3d9‬‬ ‫‪4s0‬‬ ‫‪4p0‬‬
‫]‪[Cu(NH3)4]+2 = [Ar‬‬ ‫‪3d9‬‬ ‫‪4s‬‬ ‫‪4p‬‬

‫‪NH3‬‬
‫‪four dsp2 bonds to the ligands‬‬
‫‪17‬‬

‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﻭﻫﻧﺎﻙ ﺃﻳﺿﺎ ﻋﻼﻗﺔ ﺑﻳﻥ ﺣﺎﻟﺔ ﺍﻟﺗﺄﻛﺳﺩ ﻭ ﻋﺩﺩ ﺍﻟﺗﻧﺎﺳﻕ ‪ ،.‬ﻓﺎﻟﻔﻠﺯ ﻧﻔﺳﻪ ﺑﺣﺎﻟﺗﻲ ﺗﺄﻛﺳﺩ ﻣﺧﺗﻠﻔﺗﻳﻥ ﻳﻌﻁﻲ ﺃﺣﻳﺎﻧﺎ ﻋ�ﺩﺩﻱ ﺗﻧﺎﺳ�ﻕ‬
‫ﻣﺧﺗﻠﻔ�ﻳﻥ ﻓ�ﺄﻳﻭﻥ )‪ Cu(I‬ﻭ ﺃﻳ�ﻭﻥ )‪ Ag(I‬ﻳﻛﻭﻧ�ﺎﻥ ﻣﻌﻘ�ﺩﺍﺕ ﺭﺑﺎﻋﻳ�ﺔ ﺍﻟﺳ�ﻁﻭﺡ ‪ ،‬ﻓ�ﻲ ﺣ�ﻳﻥ ﺃﻥ ﺃﻳ�ﻭﻧﻲ )‪ Cu(II‬ﻭ )‪ Ag(II‬ﻳﻛﻭﻧ�ﺎﻥ‬
‫ﻣﻌﻘﺩﺍﺕ ﺫﺍﺕ ﺷﻛﻝ ﻣﺭﺑﻊ ﻣﺳﺗﻭﻱ ‪ .‬ﻭ ﺍﻟﻣﺭﻛﺏ ]‪ [Ni(CO)4‬ﺣﻳﺙ ﺃﻥ ﺍﻟﻧﻳﻛﻝ ﺑﺣﺎﻟﺔ ﺍﻟﺗﺄﻛﺳﺩ )‪ (0‬ﻳﻛﻭﻥ ﺷﻛﻝ ﺭﺑﺎﻋﻲ ﺍﻟﺳﻁﻭﺡ ‪،‬‬

‫ﻭﻣﺭﻛﺑﺎﺕ )‪ Ni(II‬ﻋﺎﺩﺓ ﺗﻛﻭﻥ ﻣﺭﻛﺑﺎﺕ ﺫﻭ ﺷﻛﻝ ﻣﺭﺑﻊ ﻣﺳﺗﻭﻱ ‪.‬‬

‫ﻣﺛﺎﻝ‪ :‬ﺍﻷﻳﻭﻥ )‪ Cu(II‬ﻳﻛﻭﻥ ﻣﺭﻛﺑﺎﺕ ﺫﺍﺕ ﺷﻛﻝ ﺭﺑﺎﻋﻲ ﻣﺳﺗﻭﻱ ‪ ،‬ﻭ ﺍﻳﻭﻥ )‪ Cu(I‬ﻳﻛﻭﻥ ﻣﺭﻛﺑﺎﺕ ﺫﺍﺕ ﺷﻛﻝ ﺭﺑﺎﻋﻲ ﺍﻟﺳﻁﻭﺡ ‪.‬‬
‫ﻓﺳﺭ ﺫﻟﻙ ﻋﻠﻰ ﺃﺳﺎﺱ ﺍﻻﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﻬﺟﻳﻧﺔ ﺍﻟﻣﺳﺗﻌﻣﻠﺔ ؟‬

‫ﻣﺛﺎﻝ ‪ :‬ﻳﻌﺩ ﺍﻟﻣﺭﻛﺏ ]‪ [NiCI2(PPh3)2‬ﺑﺎﺭﺍﻣﻐﻧﺎﻁﻳﺳﻲ ﻓﻳﻣﺎ ﻳﻌﺩ ﺍﻟﻣﺭﻛﺏ ﺍﻟﻣﻣﺎﺛﻝ ﻷﻳﻭﻥ ‪ pd+2‬ﺩﺍﻳﺎﻣﻐﻧﺎﻁﻳﺳﻲ‪ .‬ﻓﺳﺭ ﺫﻟﻙ ؟‬

‫‪Examples of Sq.p Complexes‬‬ ‫‪Examples of Tetrahedral Complexes‬‬
‫‪[Cu(CN)4]-3‬‬
‫]‪[Cu(py)2CI2‬‬
‫]‪[CuCI2(H2O)2‬‬ ‫‪[Cu(SC(NH2)CH3)4]CI‬‬
‫]‪[Cu(acac)2‬‬ ‫‪[CuCI4]-2‬‬
‫‪[Mn(H2O)4]+2‬‬ ‫‪[Zn(CN)4]-2‬‬
‫]‪[Mn(py)2CI2‬‬ ‫‪[ZnI4]-2‬‬
‫]‪[Co(NH3)2X2‬‬ ‫‪X-=CI- ,Br- ,I-‬‬ ‫]‪[CrO3X‬‬ ‫‪X =F- ,CI-‬‬
‫]‪[Co(py)2CI2‬‬ ‫]‪[Co(CO)3NO‬‬
‫‪[Ni(CN)4]-2‬‬ ‫]‪[CoCI4]-2 , M+1[Co(NCS)4‬‬ ‫‪M+1 =K+ ,NH4+‬‬

‫ﻣﻌﻘﺩﺍﺕ ﺫﺍﺕ ﺷﻛﻝ ﻫﻧﺩﺳﻲ ﺛﻧﺎﺋﻲ ﺍﻟﻬﺭﻡ ﺍﻟﻣﺛﻠﺛﻲ )‪(trigonal bipyramidal‬‬ ‫ﺍﻟﻌﺩﺩ ﺍﻟﺗﻧﺎﺳﻘﻲ ‪5‬‬
‫ﺗﻬﺟﻳﻥ‪ dsp3‬ﺃﻭ ‪:sp3d‬‬

‫ﻳﺗﺿﻣﻥ ﺍﻟﺗﺂﺻﺭ ﻓﻲ ﺗﺭﻛﻳﺏ ﺛﻧﺎﺋﻲ ﺍﻟﻬﺭﻡ ﺍﻟﻣﺛﻠﺛﻲ ﺗﻬﺟﻳﻥ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﺫﺭﺓ ﺍﻟﻣﺭﻛﺯﻳﺔ ‪ S,PX,PY,PZ,dz2‬ﻟﻳﻌﻁﻲ ﺧﻣﺱ‬
‫ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ﻫﺟﻳﻧﺔ ﻫﻲ ﺃﻣﺎ ‪ SP3d‬ﺃﻭ ‪) dSP3‬ﺍﻋﺗﻣﺎﺩﺍ ﻋﻠﻰ ﻛﻭﻥ ﺍﻭﺭﺑﻳﺗﺎﻝ ‪ d‬ﺍﻟﻣﺳﺗﻌﻣﻝ ﺑﻧﻔﺱ ﺍﻟﻌﺩﺩ ﺍﻟﻛﻣﻲ ﻻﻭﺭﺑﻳﺗﺎﻻﺕ ‪ S‬ﻭ ‪p‬‬
‫ﺃﻭ ﻳﻘﻝ ﻋﻧﻬﺎ ﺑﻣﻘﺩﺍﺭ ﻭﺍﺣﺩ( ‪ ،‬ﻓﻣﺭﻛﺑﺎﺕ ﺍﻟﺣﺩﻳﺩ ﻭ ﺍﻟﺭﺛﻳﻧﻳﻭﻡ ﻳﻛﻭﻧﺎﻥ ﻣﺭﻛﺑﺎﺕ ﺍﻟﻛﺭﺑﻭﻧﻳﻝ ﺫﺍﺕ ﺍﻟﺻﻳﻐﺔ ‪ M(CO)5‬ﻭﺗﺗﺧﺫ ﻫﺫﻩ‬

‫ﺍﻟﺟﺯﻳﺋﺎﺕ ﺷﻛﻝ ﺛﻧﺎﺋﻲ ﺍﻟﻬﺭﻡ ﺍﻟﻣﺛﻠﺛﻲ ﻭﻳﺗﻛﻭﻥ ﻫﺫﺍ ﺍﻟﺷﻛﻝ ﺍﻟﻬﻧﺩﺳﻲ ﻋﻧﺩﻣﺎ ﺗﻛﻭﻥ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﻣﺗﻛﺎﻓﺋﺔ ﻛﻣﺎ ﻣﺑﻳﻥ ﺃﺩﻧﺎﻩ‪:‬‬

‫‪CO‬‬ ‫]‪Fe26 = [Ar‬‬ ‫‪3d6‬‬ ‫‪4s2 4p0‬‬
‫]‪FeCO5 = [Ar‬‬ ‫‪3d8‬‬ ‫‪4s 4p‬‬
‫‪CO‬‬

‫‪OC Fe‬‬

‫‪CO‬‬

‫‪CO‬‬

‫‪CO‬‬
‫‪five dsp3 bonds to the ligands‬‬

‫ﻭﺍﻟﻣﻌﻘﺩﺍﺕ ﺫﺍﺕ ﺍﻟﺗﺭﺗﻳﺏ ﺍﻟﺧﻣﺎﺳﻲ ﺛﻧﺎﺋﻲ ﺍﻟﻬﺭﻡ ﺍﻟﻣﺛﻠﺛﻲ ﺗﻛﻭﻥ ﻗﻠﻳﻠﺔ ﻭﺃﻳﺿﺎ ﻣﻥ ﺍﻷﻣﺛﻠﺔ ﻋﻠﻰ ﺫﻟﻙ ﻣﻌﻘﺩ ‪ [CdCI5]-3‬ﻭﻣﻥ‬
‫ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻷﺧﺭﻯ ﺫﺍﺕ ﺍﻟﺗﻧﺎﺳﻕ ﺍﻟﺧﻣﺎﺳﻲ ﺍﻟﺗﻲ ﻳﻛﻭﻧﻬﺎ ﺍﻟﻧﺣﺎﺱ ﻫﻲ ]‪K3[Cu(NO2)5] ,Rb[Cu(NO2)5] ,TI[Cu(NO2)5‬‬

‫‪18‬‬

‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﻣﻌﻘﺩﺍﺕ ﺧﻣﺎﺳﻳﺔ ﺍﻟﺗﻧﺎﺳﻕ ﺫﺍﺕ ﺷﻛﻝ ﻫﺭﻡ ﻣﺭﺑﻌﻲ ) ‪: (Square pyramid‬‬

‫ﺗﺭﻛﻳﺏ ﺍﻟﻬﺭﻡ ﺍﻟﻣﺭﺑﻌﻲ ﻣﺅﻛﺩ ﻟﻠﻣﺭﻛﺏ ]‪ [NiBr3((Et)3P)2‬ﻭﻳﺗﺿﻣﻥ ﺍﻟﺗﺂﺻﺭ ﻓﻲ ﻫﺫﺍ ﺍﻟﺗﺭﻛﻳﺏ ﺗﻬﺟﻳﻥ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪S ,PX ,PY‬‬
‫‪ ,PZ ,dx2-y2‬ﺑﺩﻻً ﻣﻥ ﺍﻭﺭﺑﻳﺗﺎﻝ ‪ ، dz2‬ﻭﻳﺩﻝ ﺍﻟﻌﺯﻡ ﺍﻟﻣﻐﻧﺎﻁﻳﺳﻲ ﻟﻠﻣﻌﻘﺩ ﺑﻭﺟﻭﺩ ﺍﻟﻛﺗﺭﻭﻥ ﻣﻧﻔﺭﺩ ﻟﻠﻧﻳﻛﻝ )‪ (III‬ﻛﻣﺎ ﻣﺑﻳﻥ ﺃﺩﻧﺎﻩ ‪:‬‬

‫]‪Ni+3 = [Ar‬‬ ‫‪3d7‬‬ ‫‪4s0 4p0‬‬ ‫‪Et3P‬‬ ‫‪Br‬‬
‫]‪[NiBr3(pEt3)2] = [Ar‬‬ ‫‪3d7‬‬ ‫‪4s 4p‬‬
‫‪Br‬‬

‫‪Ni‬‬

‫‪Br‬‬ ‫‪Et3P‬‬

‫)‪3Br- + 2(pEt3‬‬
‫‪five dsp3 bonds to the ligands‬‬

‫ﻭﻳﻣﺛﻝ ﺍﻟﻣﻌﻘﺩ ]‪ [VO(acac)2‬ﺃﺣﺩ ﺍﻷﻣﺛﻠﺔ ﺍﻟﻣﻌﺭﻭﻓﺔ ﺍﻟﺗﻲ ﺗﺗﺧﺫ ﺷﻛﻝ ﺍﻟﻬﺭﻡ ﺍﻟﻣﺭﺑﻌﻲ ﺣﻳﺙ ﺗﻣﺛﻝ ﺫﺭﺓ ﺍﻷﻭﻛﺳﺟﻳﻥ ﻗﻣﺔ ﺍﻟﻬﺭﻡ‪.‬‬

‫ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ﺍﻟﺛﻣﺎﻧﻳﺔ ﺍﻟﺳﻁﻭﺡ )‪ (Octahedral‬ﻭ ﺍﻟﺗﻬﺟﻳﻥ )‪: (d2sp3‬‬ ‫ﺍﻟﻌﺩﺩ ﺍﻟﺗﻧﺎﺳﻘﻲ ‪6‬‬

‫ﺑﻧﻳﺔ ﺛﻣﺎﻧﻲ ﺍﻟﺳﻁﻭﺡ ﻓﻬﻲ ﻣﻌﺭﻭﻓﺔ ﻋﻠﻰ ﻧﺣﻭ ﺛﺎﻳﺕ ﺗﻘﺭﻳﺑﺎً ﻻﻳﻭﻧﺎﺕ )‪ Pd(IV) ، Rh(III) ، Co(III‬ﻭ )‪. Pt(IV‬ﻓﻣﺛﻼً‬
‫ﺍﻟﻣﻌﻘﺩ ‪ [Cr(NH3)6]+3‬ﻳﻣﺗﻠﻙ ﺍﻳﻭﻥ )‪ Cr(III‬ﺛﻼﺛﺔ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ﻣﻧﻔﺭﺩﺓ ﻓﻲ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ ،3d‬ﻭﺑﺫﻟﻙ ﻓﺎﻻﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﺟﺎﻫﺯﺓ‬
‫ﻟﻠﺗﺂﺻﺭ ﻫﻲ ﺍﺛﻧﺎﻥ ﻣﻥ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ 3d‬ﻭ ﺍﻭﺭﺑﻳﺗﺎﻝ ‪ 4s‬ﻭ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ 4p‬ﺍﻟﺛﻼﺛﺔ ‪ ،‬ﺇﻥ ﻫﺫﻩ ﺍﻻﻭﺭﺑﻳﺗﺎﻻﺕ ﻣﺳﺗﻌﺩﺓ ﻻﺳﺗﻘﺑﺎﻝ‬
‫ﺃﺯﻭﺍﺝ ﺍﻻﻟﻛﺗﺭﻭﻧﺎﺕ ﺍﻟﺗﻲ ﺗﻬﺑﻬﺎ ﺳﺗﺔ ﻟﻳﻛﺎﻧﺩﺍﺕ ﻣﻛﻭﻧﺔ ﻣﻌﻘﺩﺍً ﺛﻣﺎﻧﻲ ﺍﻟﺳﻁﻭﺡ ﺃﻭﺍﺻﺭﻩ ﺍﻟﻬﺟﻳﻧﺔ ﻣﻥ ﻧﻭﻉ ‪، d2sp3‬ﻛﻣﺎ ﻣﺑﻳﻥ ﻓﻲ‬

‫ﺃﺩﻧﺎﻩ ‪:‬‬

‫ﺍﻳﻭﻥ ﺍﻟﻛﻭﺑﻠﺕ )‪ Co(III‬ﻭ )‪ Fe(II‬ﻳﻣﺗﻠﻙ ﺳﺗﺔ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ‪ ، d‬ﻭﻧﺗﻭﻗﻊ ﻭﺟﻭﺩ ﺃﺭﺑﻌﺔ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ﻣﻧﻔﺭﺩﺓ ﻓﻲ ﺍﻻﻳﻭﻥ ﺍﻟﺣﺭ ﻭﻣﻊ‬
‫ﺫﻟﻙ ﻋﻧﺩ ﺗﻛﻭﻳﻥ ﺳﺗﺔ ﺍﻭﺍﺻﺭ ﻗﻭﻳﺔ ﻣﻥ ﺧﻼﻝ ﺍﻟﺗﻧﺎﺳﻕ ‪ ،‬ﻳﺟﺏ ﺇﻥ ﻳﺣﺻﻝ ﻋﻠﻰ ﺭﺑﺢ ﻓﻲ ﺍﻟﻁﺎﻗﺔ ﻳﻛﻔﻲ ﻟﺟﻌﻝ ﺍﻻﻟﻛﺗﺭﻭﻧﺎﺕ ﺍﻟﺳﺗﺔ‬
‫ﺗﺯﺩﻭﺝ ﻓﻲ ﺛﻼﺛﺔ ﻣﻥ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ d‬ﻓﻘﻁ ﺗﺎﺭﻛﺎً ﺍﻻﻭﺭﺑﻳﺗﺎﻻﺕ ‪ d2sp3‬ﺟﺎﻫﺯﺓ ﻟﺗﻛﻭﻳﻥ ﺍﻷﻭﺍﺻﺭ ‪،‬ﻓﻣﺛﻼً ﻣﻌﻘﺩﺍﺕ )‪ ) Co(III‬ﻣﺛﻝ‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫‪ ،([Co(NH3)6]CI3‬ﻫﻲ ﺫﺍﺕ ﺻﻔﺎﺕ ﺩﺍﻳﺎﻣﻐﻧﺎﻁﻳﺳﻳﺔ ﻣﻣﺎ ﻳﺅﻛﺩ ﺍﻥ ﺍﻻﻟﻛﺗﺭﻭﻧﺎﺕ ﺍﻟﺳﺗﺔ ﻗﺩ ﺍﺯﺩﻭﺟﺕ ﻓﻐﻼً ﻓﻲ ﺛﻼﺛﺔ ﻣﻥ‬
‫ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ 3d‬ﻭﻛﻣﺎ ﻣﺑﻳﻥ ﺃﺩﻧﺎﻩ ‪:‬‬

‫]‪Co+3 = [Ar‬‬ ‫‪3d6‬‬ ‫‪4s0‬‬ ‫‪4p0‬‬
‫]‪[Co(NH3)6]+3= [Ar‬‬ ‫‪3d6‬‬ ‫‪4s‬‬ ‫‪4p‬‬

‫‪NH3‬‬
‫‪six d2sp3 bonds to the ligands‬‬

‫ﻭ ﻳﻁﻠﻕ ﻋﻠﻰ ﻣﻌﻘﺩﺍﺕ ﺍﻻﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﻬﺟﻳﻧﺔ ‪ d2sp3‬ﺍﺳﻡ ﻣﻌﻘﺩﺍﺕ ﺍﻻﻭﺭﺑﻳﺗﺎﻝ ﺍﻟﺩﺍﺧﻠﻲ )‪، (inner orbital Complexes‬‬
‫ﻛﻣﺎ ﻳﻣﻛﻥ ﺇﻥ ﻳﺳﻠﻙ ﻟﻳﻛﺎﻧﺩ ﺃﻳﻭﻥ ﺍﻟﺳﻳﺎﻧﻳﺩ ‪ CN-‬ﺳﻠﻭﻙ ﺍﻷﻣﻭﻧﻳﺎ ﺑﺗﻛﻭﻳﻥ ﻣﻌﻘﺩﺍﺕ ﺛﻣﺎﻧﻳﺔ ﺍﻟﺳﻁﻭﺡ ﺩﺍﻳﺎ ﻣﻐﻧﺎﻁﻳﺳﻳﺔ ﻛﻣﺎ ﻣﺑﻳﻥ ‪:‬‬

‫]‪Co+3 : [Ar‬‬ ‫‪3d‬‬ ‫‪4s 4p‬‬ ‫‪4d‬‬

‫ﻳﻣﺗﻠﻙ ﺍﻳﻭﻥ ﺍﻟﻛﻭﺑﻠﺕ )‪ Co(II‬ﺳﺑﻌﺔ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ‪ ، d‬ﻭﺑﻬﺫﺍ ﺍﻟﻌﺩﺩ ﻻ ﻳﻣﻛﻥ ﺇﺧﻼء ﺍﺛﻧﻳﻥ ﻣﻥ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ 3d‬ﻋﻥ ﻁﺭﻳﻕ ﺍﺯﺩﻭﺍﺝ‬

‫ﺍﻻﻟﻛﺗﺭﻭﻧﺎﺕ ﻓﺄﻗﺗﺭﺡ ﺑﺎﻭﻟﻧﻙ ﻁﺭﻳﻘﺔ ﻟﺗﻭﻓﻳﺭ ﺍﻻﻭﺭﺑﻳﺗﺎﻻﺕ ﻋﻥ ﻁﺭﻳﻕ ﺍﺯﺩﻭﺍﺝ ﺳﺗﺔ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ﻓﻲ ﺛﻼﺛﺔ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ﻭﺗﺭﻗﻳﺔ‬
‫ﺍﻻﻟﻛﺗﺭﻭﻥ ﺍﻟﺳﺎﺑﻊ ﺍﻟﻰ ﺍﻭﺭﺑﻳﺗﺎﻝ ﺫﻱ ﻁﺎﻗﺔ ﺃﻋﻠﻰ ‪،‬ﻭﻳﻌﺗﻘﺩ ﺇﻥ ﺍﻻﻟﻛﺗﺭﻭﻥ ﺍﻟﺫﻱ ﺭﻗﻲ ﺇﻟﻰ ﻣﺳﺗﻭﻯ ﺃﻋﻠﻰ ﻳﺳﻬﻝ ﻓﻘﺩﺍﻧﻪ ﻣﻌﻁﻳﺎً‬

‫ﻣﻌﻘﺩﺍً ﻟﻸﻳﻭﻥ )‪. Co(III‬‬

‫]‪Co+2= [Ar‬‬ ‫‪3d6 4s0 4p0‬‬ ‫‪4d‬‬
‫]‪[Co(NH3)6]+=2[Ar‬‬ ‫‪3d6 4s 4p‬‬

‫‪NH3‬‬
‫‪six d2sp3 bonds to the ligands‬‬

‫ﻣﻌﻘﺩﺍﺕ ﺗﻧﺎﺳﻘﻳﺔ ﺛﻣﺎﻧﻳﺔ ﺍﻟﺳﻁﻭﺡ ﻭ ﺍﻟﺗﻬﺟﻳﻥ ‪:sp3d2‬‬

‫ﺑﺎﻟﺭﻏﻡ ﻣﻧﺎﻥ ﺍﻏﻠﺏ ﻣﻌﻘﺩﺍﺕ ﺍﻟﻛﻭﺑﻠﺕ )‪ (III‬ﺗﻛﻭﻥ ﺩﺍﻳﺎ ﻣﻐﻧﺎﻁﻳﺳﻳﺔ ‪ ،‬ﻭﻟﻛﻥ ﺗﻡ ﺍﻛﺗﺷﺎﻑ ﺍﻣﻛﺎﻧﻳﺔ ﺗﻛﻭﻥ ﻣﻌﻘﺩ ﺑﺎﺭﺍﻣﻐﻧﺎﻁﻳﺳﻲ ﻛﻣﺎ‬
‫ﻓﻲ ‪ [CoF6]3-‬ﺣﻳﺙ ﻳﺣﺗﻭﻱ ﻋﻠﻰ ﺃﺭﺑﻌﺔ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ﻣﻧﻔﺭﺩﺓ ‪ ،‬ﻓﻘﺩ ﺗﻡ ﺗﻌﺩﻳﻝ ﺍﻟﻧﻅﺭﻳﺔ ﻓﺄﻗﺗﺭﺡ ﺇﻥ ﺃﻳﻭﻧﺎﺕ ﺍﻟﻔﻠﻭﺭﻳﺩ ﺗﺭﺗﺑﻁ‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﺑﺎﻻﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﺧﺎﺭﺟﻳﺔ ‪ 4d‬ﻟﺫﺍ ﻳﻣﻛﻥ ﺗﻣﺛﻳﻠﻪ ﻛﻣﺎ ﻳﺄﺗﻲ ‪:‬‬

‫ﻣﻥ ﻫﺫﺍ ﻧﺳﺗﻧﺗﺞ ﺍﻥ ﺍﻟﻣﻌﻘﺩ ﺧﺎﺭﺟﻲ ﺍﻟﻣﺩﺍﺭ ﻳﺗﻛﻭﻥ ﻋﻧﺩ ﺍﺳﺗﻌﻣﺎﻝ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ ، 4d‬ﺣﻳﺙ ﻳﻁﻠﻕ ﻋﻠﻰ ﻫﻛﺫﺍ ﻣﻌﻘﺩﺍﺕ ﺍﺳﻡ ﻣﻌﻘﺩﺍﺕ‬
‫ﺍﻻﻭﺭﺑﻳﺗﺎﻝ ﺍﻟﺧﺎﺭﺟﻲ )‪ (outer orbital Complexes‬ﻟﻺﺷﺎﺭﺓ ﺇﻟﻰ ﺍﺳﺗﻌﻣﺎﻝ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ sp3d2‬ﻭ ﻟﻳﺱ ‪. d2sp3‬‬

‫ﻭﺍﻳﻭﻥ ‪ Ni+2‬ﻳﻛﻭﻥ ﻣﻌﻘﺩﺍﺕ ﺛﻣﺎﻧﻳﺔ ﺍﻟﺳﻁﻭﺡ ﺫﺍﺕ ﺍﻻﻭﺭﺑﻳﺗﺎﻝ ﺍﻟﺧﺎﺭﺟﻲ ﻭ ﺫﻟﻙ ﻣﻊ ﻟﻳﻛﺎﻧﺩﺍﺕ ﻣﺛﻝ ‪ H2O‬ﻭ ‪ ، NH3‬ﻟﻛﻧﻪ ﻣﻊ‬
‫ﻟﻳﻛﺎﻧﺩ ﻣﺛﻝ ‪ CN-‬ﺍﻟﺗﻲ ﻟﻬﺎ ﻣﻳﻝ ﺷﺩﻳﺩ ﻟﺗﻛﻭﻳﻥ ﺃﻭﺍﺻﺭ ﺗﺳﺎﻫﻣﻳﺔ ﻗﻭﻳﺔ ‪،‬ﻳﻛﻭﻥ ﻣﻌﻘﺩﺍﺕ ﺭﺑﺎﻋﻳﺔ ﻣﺳﺗﻭﻳﺔ ﺫﺍﺕ ﺻﻔﺎﺕ‬

‫ﺩﺍﻳﺎﻣﻐﻧﺎﻁﻳﺳﻳﺔ ﺗﺗﺿﻣﻥ ﺍﻟﺗﺂﺻﺭ ‪. dsp2‬‬

‫• ﺍﻟﻘﻳﺎﺳﺎﺕ ﺍﻟﻣﻐﻧﺎﻁﻳﺳﻳﺔ ﻭﻋﺩﺩ ﺍﻻﻟﻛﺗﺭﻭﻧﺎﺕ ﺍﻟﻣﻧﻔﺭﺩﺓ‪:‬‬

‫ﺍﺳﺗﻌﻣﻠﺕ ﺍﻟﻘﻳﺎﺳﺎﺕ ﺍﻟﻣﻐﻧﺎﻁﻳﺳﻳﺔ ﺑﺻﻭﺭﺓ ﻭﺍﺳﻌﺔ ﻟﺗﻘﺩﻳﺭ ﻋﺩﺩ ﺍﻻﻟﻛﺗﺭﻭﻧﺎﺕ ﺍﻟﻣﻧﻔﺭﺩﺓ ﻓﻲ ﺍﻟﻣﻌﻘﺩﺍﺕ ﻭﻣﻥ ﺍﻟﺑﻳﺎﻧﺎﺕ‬
‫ﺍﻟﻣﺗﻭﻓﺭﺓ ﻳﻣﻛﻥ ﺍﻻﺳﺗﺩﻻﻝ ﻋﻠﻰ ﻋﺩﺩ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ d‬ﺍﻟﻣﺳﺗﻌﻣﻠﺔ ﻓﻲ ﺗﻛﻭﻳﻥ ﺍﻻﻭﺍﺻﺭ ﻭ ﺃﻳﺿﺎ ﻋﻠﻰ ﺍﻟﺷﻛﻝ ﺍﻟﻬﻧﺩﺳﻲ‬
‫ﻟﻠﻣﻌﻘﺩﺍﺕ ‪ .‬ﺣﻳﺙ ﺃﻁﻠﻕ ﺑﺎﻭﻟﻧﻙ ﻋﻠﻰ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﺗﻲ ﺗﻭﻓﺭ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ﻟﻠﺗﺂﺻﺭ ﻣﻥ ﺧﻼﻝ ﺍﺯﺩﻭﺍﺝ ﺍﻻﻟﻛﺗﺭﻭﻧﺎﺕ ﺑﺎﺳﻡ‬
‫ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﺗﺳﺎﻫﻣﻳﺔ )‪ . (covalent complexes‬ﻭﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﺗﻲ ﻻ ﺗﺳﺗﻌﻣﻝ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ d‬ﺍﻟﺩﺍﺧﻠﻳﺔ ﻟﻠﺗﺎﺻﺭ ﺑﺎﺳﻡ‬
‫ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻻﻳﻭﻧﻳﺔ )‪ ، (ionic complexes‬ﻛﻣﺎ ﻓﻲ ‪ [Zn(NH3)6]+2‬ﻭ ‪ [Ni(NH3)6]+2‬ﻭ ‪ [Fe(C2O4)3]-3‬ﻭ ﻋﻧﺩ‬
‫ﻧﻘﺎﺷﻧﺎ ﻟﻧﻅﺭﻳﺔ ﺍﻟﻣﺟﺎﻝ ﺍﻟﺑﻠﻭﺭﻱ )‪ (Crystal Field Theory‬ﺳﻧﺗﻌﺭﻑ ﻋﻠﻰ ﻋﺑﺎﺭﺍﺕ ﺃﺧﺭﻯ ﻭﻫﻲ ﺍﻟﻣﺟﺎﻝ ﺍﻟﻘﻭﻱ ﻭ‬

‫ﺍﻟﻣﺟﺎﻝ ﺍﻟﺿﻌﻳﻑ ﻭ ﻛﺫﻟﻙ ﻋﺑﺎﺭﺍﺕ ﺑﺭﻡ ﻭﺍﻁﺊ ﻭﺑﺭﻡ ﻋﺎﻟﻲ ‪.‬‬
‫ﺑﺎﻹﺿﺎﻓﺔ ﺇﻟﻰ ﻋﺑﺎﺭﺍﺕ ﺍﻟﺩﺍﻳﺎﻣﻐﻧﺎﻁﻳﺳﻲ ﻭ ﺍﻟﺑﺎﺭﺍﻣﻐﻧﻁﻳﺳﻲ ﺍﻟﺗﻲ ﻳﻣﻛﻥ ﺇﻥ ﺗﻣﻳﻳﺯ ﺑﻬﺎ ﺍﻟﻣﻌﻘﺩﺍﺕ ‪ ،‬ﻟﻛﻥ ﻓﻲ ﺣﺎﻟﺔ‬
‫ﺍﻻﻳﻭﻧﺎﺕ ﺍﻟﻔﻠﺯﻳﺔ ﺍﻟﺗﻲ ﺗﻣﺗﻠﻙ ﻋﺩﺩﺍً ﻓﺭﺩﻳﺎً ﻣﻥ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ‪ d‬ﻛﻣﺎ ﻓﻲ ‪ d5‬ﻣﺛﻝ ‪ Fe+3‬ﺍﻟﺫﻱ ﺳﻳﺗﺻﻑ ﺑﺎﻟﺧﻭﺍﺹ‬
‫ﺍﻟﺑﺎﺭﺍﻣﻐﻧﺎﻁﻳﺳﻳﺔ ﻓﻲ ﺟﻣﻳﻊ ﺍﻷﺣﻭﺍﻝ ﺑﻐﺽ ﺍﻟﻧﻅﺭ ﻋﻥ ﺗﺄﺛﻳﺭ ﺍﻟﻠﻳﻛﺎﻧﺩ ‪ ،‬ﻭﺑﻬﺫﻩ ﺍﻟﺣﺎﻟﺔ ﻓﺄﻥ ﻣﻌﺭﻓﺔ ﺍﻟﺧﻭﺍﺹ ﺍﻟﻣﻐﻧﺎﻁﻳﺳﻳﺔ‬
‫ﻣﻔﻳﺩﺓ ﻓﻣﺛﻼً ﻳﺣﺗﻭﻱ ﺍﻻﻳﻭﻥ ﺍﻟﺑﺎﺭﺍﻣﻐﻧﺎﻁﻳﺳﻲ ‪ [Fe(H2O)6]+3‬ﻋﻠﻰ ﺧﻣﺱ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ﻣﻧﻔﺭﺩﺓ ﺑﻳﻧﻣﺎ ﻳﺣﺗﻭﻱ ﺍﻻﻳﻭﻥ‬

‫ﺍﻟﺑﺎﺭﺍﻣﻐﻧﺎﻁﻳﺳﻲ ‪ [Fe(CN)6]-3‬ﻋﻠﻰ ﺇﻟﻛﺗﺭﻭﻥ ﻣﻧﻔﺭﺩ ﻭﺍﺣﺩ ﻭﻳﻣﻛﻥ ﺗﻣﺛﻳﻝ ﻫﺫﻩ ﺍﻟﻣﻌﻘﺩﺍﺕ ﻛﻣﺎ ﻳﺄﺗﻲ ‪:‬‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫‪Fe+3‬‬ ‫]‪= [Ar‬‬ ‫‪3d5‬‬ ‫‪4s0 4p0‬‬
‫‪3d5‬‬ ‫‪4s 4p‬‬
‫‪4d‬‬

‫]‪[Fe(H2O)6]+3 = [Ar‬‬

‫‪3d5‬‬ ‫‪H2O‬‬ ‫‪4d‬‬
‫‪six sp3d2 bonds to the ligands‬‬

‫‪4s 4p‬‬

‫]‪[Fe(CN)6]-3 = [Ar‬‬

‫‪CN-‬‬
‫‪six d2sp3 bonds to the ligands‬‬

‫• ﻣﻌﻘﺩﺍﺕ ﺍﻻﻭﺭﺑﻳﺗﺎﻝ ﺍﻟﺩﺍﺧﻠﻲ ﻭ ﻣﻌﻘﺩﺍﺕ ﺍﻻﻭﺭﺑﻳﺗﺎﻝ ﺍﻟﺧﺎﺭﺟﻲ ‪:‬‬

‫ﺇﻥ ﻣﻌﻘﺩﺍﺕ ﻣﺛﻝ ‪ [Zn(NH3)6]+2‬ﻭ ‪ [Fe(C2O4)3]-3‬ﻻ ﻳﺻﺢ ﺍﻋﺗﺑﺎﺭﻫﺎ ﻣﻔﺗﻘﺭﺓ ﻛﻠﻳﺎً ﻟﺑﻌﺽ ﺍﻟﺧﺻﺎﺋﺹ ﺍﻟﺗﺳﺎﻫﻣﻳﺔ‬
‫‪ ،‬ﺇﺫ ﺇﻥ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ 4d‬ﻓﻲ ﻫﺫﻩ ﺍﻟﺣﺎﻟﺔ ﻳﺟﺏ ﺇﻥ ﺗﻛﻭﻥ ﺫﺍﺕ ﻁﺎﻗﺔ ﻣﻧﺧﻔﺿﺔ ﺗﺅﻫﻠﻬﺎ ﻻﻥ ﺗﺷﺗﺭﻙ ﺇﻟﻰ ﺣﺩ ﻣﻌﻳﻥ ﻓﻲ‬
‫ﺗﺂﺻﺭ ﺗﺳﺎﻫﻣﻲ ‪ ،‬ﻓﺎﻟﺧﻳﺎﺭ ﺇﻣﺎﻡ ﻣﻌﻘﺩﺍﺕ ‪ Zn+2‬ﺇﻣﺎ ﺃﻥ ﺗﻛﻭﻥ ﻣﻌﻘﺩﺍﺕ ﺭﺑﺎﻋﻳﺔ ﺍﻟﺳﻁﻭﺡ ﺍﻭ ﺛﻣﺎﻧﻳﺔ ﺍﻟﺳﻁﻭﺡ ﺫﺍﺕ‬

‫ﺍﻭﺭﺑﻳﺗﺎﻝ ﺧﺎﺭﺟﻲ ‪ .‬ﻭﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﺭﺑﺎﻋﻳﺔ ﺍﻟﺳﻁﻭﺡ ﻟﻬﺫﺍ ﺍﻻﻳﻭﻥ ﺗﻔﺿﻝ ﻋﻠﻰ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﺛﻣﺎﻧﻳﺔ ﺍﻟﺳﻁﻭﺡ ﻓﺎﻟﻣﻌﻘﺩﺍﺕ‬
‫ﺍﻟﺭﺑﺎﻋﻳﺔ ﺗﻘﻠﻝ ﻣﻥ ﺗﻧﺎﻓﺭ ﻟﻳﻛﺎﻧﺩ – ﻟﻳﻛﺎﻧﺩ ‪ .‬ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﺭﺑﺎﻋﻳﺔ ﺍﻟﻣﺳﺗﻭﻳﺔ ﺗﺷﺗﻬﺭ ﺑﻬﺎ ﺃﻳﺿﺎ ﺍﻳﻭﻧﺎﺕ ‪pt+2، Pd+2‬‬
‫‪ Au+3،‬ﻭ ‪ Cu+2‬ﺑﺣﻳﺙ ﻳﻣﻛﻥ ﺗﻭﻓﻳﺭ ﺍﻭﺭﺑﻳﺗﺎﻝ ‪ d‬ﻋﻥ ﻁﺭﻳﻕ ﺍﺯﺩﻭﺍﺝ ﺍﻻﻟﻛﺗﺭﻭﻧﺎﺕ ﻓﻲ ﺟﻣﻳﻊ ﻫﺫﻩ ﺍﻻﻳﻭﻧﺎﺕ ﺑﺎﺳﺗﺛﻧﺎء‬
‫ﺍﻳﻭﻥ ‪ Cu+2‬ﻓﺎﻹﻟﻛﺗﺭﻭﻥ ﺍﻟﺗﺎﺳﻊ ﻳﻣﻛﻥ ﻓﻲ ﺍﻳﻭﻥ ‪ [Cu(NH3)4]+2‬ﻗﺩ ﻳﺭﻗﻰ ﺍﻟﻰ ﺍﻭﺭﺑﻳﺗﺎﻝ ﺫﻱ ﻁﺎﻗﺔ ﻋﺎﻟﻳﺔ ﻣﻣﺎ ﻳﺳﻬﻝ‬
‫ﻓﻘﺩﺍﻧﻪ ﻭﻳﺗﺣﻭﻝ ﺇﻟﻰ ‪ ، Cu+3‬ﻟﻛﻥ ﺍﻟﻭﺍﻗﻊ ﺻﻌﻭﺑﺔ ﺣﺻﻭﻝ ﻫﺫﻩ ﺍﻷﻛﺳﺩﺓ ﻻﻳﻭﻥ ‪ . Cu+2‬ﻭﺍﻟﻔﺷﻝ ﻓﻲ ﺗﻔﺳﻳﺭ ﺍﻟﺗﺂﺻﺭ ﻓﻲ‬

‫ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻟﻧﺣﺎﺱ ﺍﻟﻣﺳﺗﻘﺭﺓ ﻫﻭ ﺇﺣﺩﻯ ﻧﻘﺎﻁ ﺍﻟﺿﻌﻑ ﺍﻟﺭﺋﻳﺳﻳﺔ ﻓﻲ ﻧﻅﺭﻳﺔ ﺁﺻﺭﺓ ﺍﻟﺗﻛﺎﻓﺅ ‪.‬ﻛﻣﺎ ﺇﻥ ﺍﻟﻧﻅﺭﻳﺔ ﺗﺧﻣﻥ‬
‫ﺍﻟﻌﺩﺩ ﺍﻟﺗﻧﺎﺳﻘﻲ ‪ 5‬ﻷﻧﻅﻣﺔ ‪ d8‬ﺫﺍﺕ ﺍﻟﺑﺭﻡ ﺍﻟﻭﺍﻁﺊ ﻋﻠﻰ ﻋﻛﺱ ﻣﺎ ﻣﻌﺭﻭﻑ ﻋﻥ ﻫﺫﻩ ﺍﻷﻧﻅﻣﺔ ﺍﻟﺗﻲ ﺛﺑﺕ ﺃﻧﻬﺎ ﺗﻌﻁﻲ ﺍﻟﻌﺩﺩ‬

‫ﺍﻟﺗﻧﺎﺳﻘﻲ ‪.4‬‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫‪ ‬ﻧﻅﺭﻳﺔ ﺍﻟﻣﺟﺎﻝ ﺍﻟﺑﻠﻭﺭﻱ ‪(Crystal Field Theory ( C.F.T) -:‬‬

‫ﺗﻔﺗﺭﺽ ﻫﺫﻩ ﺍﻟﻧﻅﺭﻳﺔ ﻋﻠﻰ ﺍﻥ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﻔﻠﺭﻳﺔ ﻋﺑﺎﺭﺓ ﻫﻥ ﺗﺩﺍﺧﻝ ﺍﻟﻛﺗﺭﻭﺳﺗﺎﺗﻳﻛﻲ ) ﻳﻌﻧﻲ ﺗﺂﺻﺭ ﺍﻳﻭﻧﻲ ( ﺑﻳﻥ‬
‫ﺍﻟﺫﺭﺓ ﺍﻟﻣﺭﻛﺯﻳﺔ )ﺗﻌﺗﺑﺭ ﻛﺷﺣﻧﺔ ﻧﻘﻁﻳﺔ ﻣﻭﺟﺑﺔ ﺗﺣﺗﻭﻱ ﻋﻠﻰ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ d‬ﺍﻟﺧﻣﺳﺔ ( ﻭ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﻣﺣﻳﻁﺔ ﺑﻬﺎ‬
‫)ﻛﺷﺣﻧﺔ ﻧﻘﻁﻳﺔ ﺳﺎﻟﺑﺔ ﺗﻧﺟﺫﺏ ﻧﺣﻭ ﺍﻟﺷﺣﻧﺎﺕ ﺍﻟﻣﻭﺟﺑﺔ ﻭ ﻳﺣﺩﺙ ﺍﻟﺗﺂﺻﺭ ‪ ،‬ﻭﻗﺩ ﻓﺳﺭﺕ ﻫﺫﻩ ﺍﻟﻧﻅﺭﻳﺔ ﺍﻻﻟﻭﺍﻥ ﻭ ﺍﻟﺳﻠﻭﻙ‬

‫ﺍﻟﻣﻐﻧﺎﻁﻳﺳﻲ ﻭ ﺍﻟﻁﻳﻔﻲ ﻟﻠﻣﻌﻘﺩﺍﺕ‪.‬‬

‫ﻭﻟﻔﻬﻡ ﻧﻅﺭﻳﺔ ﺍﻟﻣﺟﺎﻝ ﺍﻟﺑﻠﻭﺭﻱ ﻣﻥ ﺍﻟﺿﺭﻭﺭﻱ ﻣﻌﺭﻓﺔ ﺍﻻﺗﺟﺎﻫﺎﺕ ﺍﻟﻔﺭﺍﻏﻳﺔ ﻻﻭﺭﺑﻳﺗﺎﻻﺕ ‪-: d‬‬

‫ﻣﻥ ﺧﻼﻝ ﺗﻣﺛﻳﻝ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ d‬ﺍﻟﺧﻣﺳﺔ ﻧﻼﺣﻅ ﺃﻥ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ dyz,dxy,dxz‬ﺗﻘﻊ ﻣﺎﺑﻳﻥ ﺍﻟﻣﺣﺎﻭﺭ ‪،‬ﺃﻣﺎ ﺍﻭﺭﺑﻳﺗﺎﻟﻲ ‪dx2-y2‬‬
‫ﻭ‪ dz2‬ﺗﻘﻊ ﻛﺛﺎﻓﺗﻬﻣﺎ ﺍﻻﻟﻛﺗﺭﻭﻧﻳﺔ ﻋﻠﻰ ﺍﻟﻣﺣﺎﻭﺭ ﻟﺫﻟﻙ ﻋﻧﺩ ﺍﻗﺗﺭﺍﺏ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﻣﻥ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ d‬ﺍﻟﺧﻣﺳﺔ ﻧﺗﻭﻗﻊ ﺣﺻﻭﻝ‬
‫ﺍﻧﻔﺻﺎﻡ ‪ splitting‬ﺃﻭ ﺍﻧﺣﻼﻝ ﻭ ﺍﻟﺗﺄﺛﻳﺭ ﺍﻟﺩﻗﻳﻕ ﻟﻬﺫﻩ ﺍﻟﻅﺎﻫﺭﺓ ﻋﻠﻰ ﻁﺎﻗﺎﺕ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ d‬ﻳﻌﺗﻣﺩ ﺗﺭﺗﻳﺏ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ‬

‫ﺣﻭﻝ ﺍﻻﻳﻭﻥ ﺍﻟﻔﻠﺯﻱ ) ﺍﻟﺷﻛﻝ ﺍﻟﻔﺭﺍﻏﻲ ( ‪.‬‬
‫‪ ‬ﺗﺄﺛﻳﺭ ﺍﻟﻣﺟﺎﻝ ﺍﻟﺑﻠﻭﺭﻱ ﻟﻠﻣﻌﻘﺩﺍﺕ ﺍﻟﺛﻣﺎﻧﻳﺔ ﺍﻟﺳﻁﻭﺡ ‪(splitting of d orbitals in octahedral complexes) -:‬‬
‫ﻟﻧﺄﺧﺫ ﺫﺭﺓ ﻣﺭﻛﺯﻳﺔ ‪ M‬ﻣﺣﺎﻁﺔ ﺑﺳﺕ ﻧﻘﺎﻁ ﻣﺷﺣﻭﻧﺔ ﺍﻟﻣﺗﻣﺛﻠﺔ ﺑﺎﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﻭﺑﺳﺑﺏ ﺍﻟﺗﺩﺍﺧﻝ ﺍﻻﻟﻛﺗﺭﻭﺳﺗﺎﺗﻳﻛﻲ ﻋﻠﻰ‬
‫ﺍﻻﺣﺩﺍﺛﻳﺎﺕ ‪، X,Y,Z‬ﻟﺫﺍ ﻓﺄﻥ ﺍﻻﻟﻛﺗﺭﻭﻧﺎﺕ ﺗﻛﺗﺳﺏ ﺍﺳﺗﻘﺭﺍﺭﺍ ﻧﺳﺑﻳﺎً ﻓﻲ ﺍﻻﻭﺭﺑﻳﺗﺎﻻﺕ ‪ dyz,dxy,dxz‬ﻭ ﺍﻟﺗﻲ ﻳﻁﻠﻕ ﻋﻠﻳﻬﺎ‬
‫)‪ (t2g‬ﻷﻥ ﻓﺻﻭﺻﻬﺎ ﺗﺗﺟﻪ ﻣﺎﺑﻳﻥ ﺍﻻﺣﺩﺍﺛﻳﺎﺕ ﻭﻳﺣﺻﻝ ﻋﻛﺱ ﺫﻟﻙ ﻷﻭﺭﺑﻳﺗﺎﻟﻲ ‪ dz2,dx2-y2‬ﺍﻟﺫﻳﻥ ﻳﺗﺟﻬﺎﻥ ﻣﺑﺎﺷﺭﺓ ﻧﺣﻭ‬

‫ﺍﻟﺷﺣﻧﺎﺕ ﺍﻟﺳﺎﻟﺑﺔ ﻭ ﻳﻁﻠﻕ ﻋﻠﻳﻬﺎ ﺑﺄﻭﺭﺑﻳﺗﺎﻟﻲ )‪. (eg‬‬

‫‪23‬‬

‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫‪0.6Δ=+6Dq‬‬
‫‪Δor 10Dq‬‬

‫‪-0.4Δ =-4Dq‬‬

‫ﻧﻼﺣﻅ ﺃﻥ ﻁﺎﻗﺔ ﺍﻭﺭﺑﻳﺗﺎﻟﻲ ‪ eg‬ﺗﺭﺗﻔﻊ )‪ 1.5‬ﻣﺭﺓ( ﺑﻘﺩﺭ ﺍﻧﺧﻔﺎﺽ ﻁﺎﻗﺔ ﺍﻭﺭﺑﻳﺗ�ﺎﻝ ‪ t2g‬وﻴطﻠـق ﻋﻠـﻰ اﻟﻤﺴـﺎﻓﺔ اﻟﺘـﻲ ﺘﻔﺼـﻝ ﺒـﻴن‬

‫ﻤدا ارت اﻟﻤﺴﺘوى )‪ (eg‬وﻤدا ارت اﻟﻤﺴـﺘوى)‪ (t2g‬ﺒﺎﻟﻛﻤﻴـﺔ ) ‪ (10Dq‬أو ) ‪ ( ∆0‬ﻤﻬﻤـﺎ ﻛـﺎن ﻤﻘـدارﻫﺎ ‪ .‬وﺒﺘﻐﻴﻴـر ﻗﻴﻤﺘـﻪ ﻤـن‬

‫ﻤﻌﻘد ﻷﺨر ﻤﻌﺘﻤدﻩ ﻋﻠﻰ ﻨوع اﻟﻠﻴﻛﺎﻨدات وﻨوع اﻷﻴون اﻟﻔﻠزي وﺸﺤﻨﺘﻪ وﻨﺼف ﻗطرﻩ ‪.‬‬

‫ﻗﻴﺎس ﻤﻘدار طﺎﻗﺔ اﻨﻔﺼﺎم اﻟﻤﺠﺎﻝ اﻟﺒﻠوري ‪-: (10Dq ) Δ‬‬

‫ﻴﻤﻛن ﻗﻴﺎس ﻗﻴﻤﺔ اﻟﻤﻘدار ﻋن طرﻴق ﻤﻌرﻓﺔ اﻟطﺎﻗﺔ اﻟﻼزﻤـﺔ ﻹﻨﺘﻘـﺎﻝ اﻟﻛﺘـرون ﻤـن اﻟﻤﺴـﺘوى )‪ (t2g‬اﻟﺤﺎﻟـﺔ اﻟﻤﺴـﺘﻘرة إﻟـﻰ‬
‫)‪ (eg‬اﻟﺤﺎﻟﺔ اﻟﻤﺜﺎرة وﻤن اﻟﻤﻌروف أن اﻹﻟﻛﺘروﻨﺎت ﺘﻤﻴﻝ ﻷن ﺘﺴﺘﻘر ﻓﻲ اﻟﻤـدا ارت اﻷﻗـﻝ ﻓـﻲ اﻟطﺎﻗـﺔ وأﻴﻀـﺎً ﺘﻤﻴـﻝ ﺒـﺄن ﺘﻛـون‬

‫طﻠﻴﻘﺔ وﻤﻨﻔردة ﺤﺴب ﻗﺎﻋدة ﻫوﻨد ‪.‬‬

‫) ‪ (Ti3+‬وﺘرﻛﻴﺒـﻪ اﻹﻟﻛﺘروﻨـﻲ )‪ (d1‬اﻟـذي ﻴﺤﺘـﻝ ﻓﻴـﻪ اﻹﻟﻛﺘـرون‬ ‫‪ [Ti(H‬ﻓـﺈن أﻴـون اﻟﺘﻴﺘـﺎﻨﻴوم‬ ‫‪2‬‬ ‫‪3+‬‬ ‫ﻓﻔـﻲ ﺤﺎﻟـﺔ اﻟﻤﻌﻘـد‬

‫])‪O‬‬

‫اﻟﻤﺴﺘوى اﻷﻗﻝ ﻓﻲ اﻟطﺎﻗﺔ اﻟﻤﺴﺘوى)‪ ، (t2g‬ﻓﻨﺠد أن ﻋﻤﻠﻴﺔ اﻨﺘﻘﺎﻝ اﻹﻟﻛﺘرون ﻤن اﻟﺤﺎﻟﺔ اﻟﻤﺴﺘﻘرة اﻟﻰ اﻟﺤﺎﻟﺔ اﻟﻤﺜﺎرة‬

‫ﺤﻴث ﻴﺘﺤوﻝ ﻟون اﻟﻤﺤﻠوﻝ اﻴون اﻟﺘﻴﺘـﺎﻨﻴوم) ‪ (Ti 3+‬ﻟﻠﺒﻨﻔﺴـﺠﻲ ﻨﺘﻴﺠـﺔ ﻻﻣﺗﺻ�ﺎﺹ ﻁﺎﻗ�ﺔ ﺿ�ﻭﺋﻳﺔ ﻟﻛ�ﻲ ﻳﻧﺗﻘ�ﻝ ﻫ�ﺫﺍ ﺍﻻﻟﻛﺗ�ﺭﻭﻥ‬
‫ﺍﻟﻭﺣﻳ�ﺩ ﻣ�ﻥ ﺍﻭﺭﺑﻳﺗ�ﺎﻻﺕ ‪ t2g‬ﺍﻟ�ﻰ ﺍﺣ�ﺩ ﺍﻭﺭﺑﻳﺗ�ﺎﻻﺕ ‪ eg‬ﻭ ﻳﻌﻁ�ﻲ ﻁﻳ�ﻑ ﻫ�ﺫﺍ ﺍﻟﻣﻌﻘ�ﺩ ﺣﺯﻣ�ﺔ ﺍﻣﺗﺻ�ﺎﺹ ﻋﻧ�ﺩ ‪ 20,400‬ﺳ�ﻡ ‪۱-‬‬

‫)‪ (500nm‬ﺍﻟﺗﻲ ﺗﻣﺛﻝ ﻗﻳﻣﺔ ‪ Δ₀‬ﻛﻣﺎ ﻣﻣﺛﻝ ﺑﺎﻟﺷﻛﻝ‪.‬‬

‫‪24‬‬

‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﺗﻣﻳﻝ ﺍﻻﻟﻛﺗﺭﻭﻧﺎﺕ ﻓﻲ ﺣﺎﻟﺔ ﺍﻟﺳﻛﻭﻥ ﺇﻟﻰ ﺇﺷﻐﺎﻝ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ t2g‬ﻗﺑﻝ ﺍﻭﺭﺑﻳﺗﺎﻟﻲ ‪ eg‬ﻭﻫﺫﺍ ﺍﻟﻣﻠﺊ ﺍﻟﺗﺩﺭﻳﺟﻲ ﻳﻌﻁﻲ ﺍﺳﺗﻘﺭﺍﺭﻳﺔ‬
‫ﺗﺿ�ﺎﻑ ﺇﻟ�ﻰ ﺍﺳ�ﺗﻘﺭﺍﺭﻳﺔ ﺍﻻﻳ�ﻭﻥ ﺍﻟﺣ�ﺭ ﻭﻫ�ﺫﻩ ﺍﻟﻁﺎﻗ�ﺔ ﺍﻻﺿ�ﺎﻓﻳﺔ ﺗ�ﺩﻋﻰ ﻁﺎﻗ�ﺔ ﺍﺳ�ﺗﻘﺭﺍﺭ ﺍﻟﻣﺟ�ﺎﻝ ﺍﻟﺑﻠ�ﻭﺭﻱ ‪(Crystal field‬‬

‫)‪ ، Stabilization Energy‬ﻭ ﺗﺣﺳﺏ ﺍﻟﻁﺎﻗﺔ ﺍﻟﻛﻠﻳﺔ ﻷﺳﺗﻘﺭﺍﺭﻳﺔ ﺍﻟﻣﺟﺎﻝ ﺍﻟﺑﻠﻭﺭﻱ ﻣﻥ ﺍﻟﻣﻌﺎﺩﻟﺔ ‪:‬‬

‫‪CFSE = -0.4 Δo nt2g + 0.6 Δo neg‬‬

‫ﺣﻳﺙ ‪ nt2g , neg‬ﻫﻲ ﻋﺩﺩ ﺍﻻﻟﻳﻛﺗﺭﻭﻧﺎﺕ ﺍﻟﺗﻲ ﺗﺷﻐﻝ ﺍﻟﻣﺩﺍﺭﻳﻥ ‪ t2g ، eg‬ﻋﻠﻰ ﺍﻟﺗﻭﺍﻟﻲ‪.‬‬

‫ﻭ ﻁﺎﻗﺔ ﺃﺳﺗﻘﺭﺍﺭﻳﺔ ﺍﻟﻣﺟﺎﻝ ﺍﻟﺑﻠﻭﺭﻱ ﺗﺳﺎﻭﻱ ﺻﻔﺭﺍ ﻓﻲ ﺣﺎﻟﺔ ﺍﻷﻳﻭﻧﺎﺕ ﺫﺍﺕ ﺍﻟﺗﺭﻛﻳﺏ ‪ ، d0 ، d10 ،‬ﻓﻲ ﻣﺟﺎﻻﺕ ﻛﻝ ﻣﻥ‬
‫ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﺿﻌﻳﻔﺔ ﻭ ﺍﻟﻘﻭﻳﺔ ‪.‬‬

‫ﻭﻟﻠﺗﺭﺗﻳﺏ ﺍﻻﻟﻛﺗﺭﻭﻧﻲ ‪ d4‬ﻳﻅﻬﺭ ﺍﺣﺗﻣﺎﻻﻥ ﻟﻬﺫﻩ ﺍﻟﺣﺎﻟﺔ ﻫﻲ ﺣﺎﻟﺔ ‪ (1) -:‬ﺍﻟﻣﺟﺎﻝ ﺍﻟﺿﻌﻳﻑ)‪ (weak field‬ﺣﻳﺙ ﺍﻟﻔﺭﻕ ﺑﻳﻥ‬
‫ﻁﺎﻗﺔ ﺍﻟﻣﺳﺗﻭﻳﻳﻥ )‪ (t2g),(eg‬ﺻﻐﻳﺭ ﺍﺫﺍ ﻣﺎﻗﻭﺭﻧﺕ ﺑﻁﺎﻗﺔ ﺍﻻﺯﺩﻭﺍﺝ ﺍﻻﻟﻛﺗﺭﻭﻧﻲ ‪(p) Electron pairing energy :‬‬

‫ﻭﻫﻲ ﺍﻟﻁﺎﻗﺔ ﺍﻟﻼﺯﻣﺔ ﻻﺯﺩﻭﺍﺝ ﺍﻟﻛﺗﺭﻭﻧﺎﻥ ﻓﻲ ﻣﺩﺍﺭ ﻭﺍﺣﺩ ‪ ،‬ﻓﺈﺫﺍ ﻛﺎﻧﺕ ﻛﺑﻳﺭﺓ ﻓﺎﻹﻟﻛﺘرون اﻟ ارﺒﻊ ﺴﻴدﺨﻝ أﺤد اﻟﻤدا ارت اﻟﻤوﺠودة‬
‫ﻓﻲ اﻟﻤﺴﺘوى )‪ (eg‬ﺒدﻻً ﻤن أن ﻴزدوج ﻓﻲ اﻟﻤدا ارت )‪ . (t2g‬وﺘﻛون طﺎﻗﺔ اﻻﺴﺘﻘ ارر ﻟﻠﻤﺠﺎﻝ اﻟﻀﻌﻴف ﻫﻲ )‬

‫‪ (3x − 4Dq + 6Dq = −6Dq‬وﻴﻛون اﻟﺘوزﻴﻊ اﻻﻟﻴﻛﺘروﻨﻲ‪ . (t32g eg1)= d4‬وﻴﻤﻛن ﺤﺴﺎب طﺎﻗﺔ إﺴﺘﻘ ارر اﻟﻤﺠﺎﻝ‬

‫اﻟﺒﻠوري ﻟﻠﺘ ارﻛﻴب ﻤن )‪ (d5‬إﻟﻰ )‪ (d7‬ﻓﻲ ﺤﺎﻟﺔ اﻟﻤﺠﺎﻝ اﻟﻀﻌﻴف ﺒﻨﻔس اﻟطرﻴﻘﺔ ‪.‬‬

‫‪25‬‬

‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫)‪ (2‬ﺣﺎﻟﺔ ﺍﻟﻣﺟﺎﻝ ﺍﻟﻘﻭﻱ )‪: (strong field‬ﺣﻳﺙ ﺍﻟﻔﺭﻕ ﺑﻳﻥ ﻁﺎﻗﺔ ﺍﻟﻣﺳﺗﻭﻳﻳﻥ ﻛﺑﻳﺭﺓ ﺑﺣﻳﺙ ﺗﻛﻭﻥ ﺍﻟﻁﺎﻗﺔ ﺍﻟﻼﺯﻣﺔ ﻻﻧﺗﻘﺎﻝ‬
‫ﺍﻻﻟﻛﺗﺭﻭﻥ ﺍﻟﻰ ﺍﺣﺩﻯ ﻣﺩﺍﺭﺍﺕ ‪ eg‬ﺍﻋﻠﻰ ﻣﻥ ﻁﺎﻗﺔ ﺍﻻﺯﺩﻭﺍﺝ )‪ (Δ₀ > P‬ﻟﻬﺫﺍ ﺍﻻﻟﻛﺗﺭﻭﻥ ﻳﺯﺩﻭﺝ ﺑﺩﻻً ﻣﻥ ﺍﻻﻧﺗﻘﺎﻝ ﺍﻟﻰ ﺍﻭﺭﺑﻳﺗﺎﻝ‬

‫‪. eg‬‬

‫ﺃﻣﺛﻠﺔ‪ :‬ﺍﻛﺗﺏ ﺍﻟﺗﻭﺯﻳﻊ ﺍﻻﻟﻛﺗﺭﻭﻧﻲ ﻟﻸﻳﻭﻧﺎﺕ ‪ d2 , d3 , d4‬ﻓﻲ ﻣﺟﺎﻝ ﻟﻳﻛﺎﻧﺩﻱ ﺛﻣﺎﻧﻲ ﺍﻷﻭﺟﻪ )‪ (octahedral‬ﻗﻭﻱ ﻭ‬
‫ﺿﻌﻳﻑ ‪ ،‬ﺛﻡ ﺃﺣﺳﺏ ﻁﺎﻗﺔ ﺍﺳﺗﻘﺭﺍﺭ ﺍﻟﻣﺟﺎﻝ ﺍﻟﺑﻠﻭﺭﻱ ‪ CFSE‬؟‬

‫‪d2 : (t2g)2(eg)0‬‬ ‫‪d3 : (t2g)3(eg)0‬‬
‫‪CFSE =2 x – 0.4Δo = -0.8 Δo‬‬ ‫‪CFSE = 3 x – 0.4Δo = -1.2 Δo‬‬

‫)‪d4 : (t2g)4(eg)0 (low spin‬‬ ‫)‪d4 : (t2g)3(eg)1 (high spin‬‬

‫‪CFSE = 4 * – 0.4Δo + p = -1.6Δo + p CFSE = 3x-0.4Δ₀ + 1x o.6 =-0.6Δ₀‬‬

‫‪Δo > p‬‬ ‫‪Δo < p‬‬

‫ﻭﻳﺑﻳﻥ ﺍﻟﺟﺩﻭﻝ ﺍﻟﺗﺎﻟﻲ ﻣﻠﺧﺹ ﻟﺗﺭﻛﻳﺏ ﻭﻁﺎﻗﺔ ﺍﺳﺗﻘﺭﺍﺭ ﺍﻟﻣﺟﺎﻝ ﺍﻟﺑﻠﻭﺭﻱ )‪ (CFSE‬ﻭﻋﺩﺩ ﺍﻻﻟﻛﺗﺭﻭﻧﺎﺕ ﺍﻟﻣﺯﺩﻭﺟﺔ ﻟﻠﺗﺭﺍﻛﻳﺏ ﻣﻥ‬

‫‪ d1→d10‬ﻓﻲ ﺣﺎﻟﺗﻲ ﺍﻟﻣﺟﺎﻝ ﺍﻟﺿﻌﻳﻑ ﻭ ﺍﻟﻣﺟﺎﻝ ﺍﻟﻘﻭﻱ ‪:‬‬

‫‪26‬‬

‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫‪Weak Field‬‬ ‫‪Strong Field‬‬

‫‪d configrution Unpaird CFSE‬‬ ‫‪d configrution Unpair CFSE‬‬

‫‪electron‬‬ ‫‪d‬‬

‫‪d1 t2g1 eg0‬‬ ‫‪1‬‬ ‫‪-0.4 Δ₀‬‬ ‫‪d1 t2g1 eg0‬‬ ‫‪1‬‬ ‫‪-0.4 Δ₀‬‬

‫‪d2 t2g2 eg0‬‬ ‫‪2‬‬ ‫‪-0.8 Δ₀‬‬ ‫‪d2 t2g2 eg0‬‬ ‫‪2‬‬ ‫‪-0.8 Δ₀‬‬

‫‪d3 t2g3 eg0‬‬ ‫‪3‬‬ ‫‪-1.2 Δ₀‬‬ ‫‪d3 t2g3 eg0‬‬ ‫‪3‬‬ ‫‪-1.2 Δ₀‬‬

‫‪d4 t2g3 eg1‬‬ ‫‪4‬‬ ‫‪-0.6Δ₀‬‬ ‫‪d4 t2g4 eg0‬‬ ‫‪2‬‬ ‫‪-1.6Δ₀ +p3‬‬

‫‪d5 t2g3 eg2‬‬ ‫‪5‬‬ ‫‪0Δ₀‬‬ ‫‪d5 t2g5 eg0‬‬ ‫‪1‬‬ ‫‪-2Δ₀+2p‬‬

‫‪d6 t2g4 eg2‬‬ ‫‪4‬‬ ‫‪-0.4Δ₀+p‬‬ ‫‪d6 t2g6 eg0‬‬ ‫‪0‬‬ ‫‪-2.4Δ₀ +3p‬‬

‫‪d7 t2g5 eg2‬‬ ‫‪3‬‬ ‫‪-0.8Δ₀ +2p d7‬‬ ‫‪t2g6 eg1‬‬ ‫‪1‬‬ ‫‪-1.8Δ₀ +3p‬‬
‫‪d8 t2g6 eg2‬‬ ‫‪2‬‬ ‫‪-1.2Δ₀+3p d8‬‬ ‫‪t2g6 eg2‬‬ ‫‪2‬‬ ‫‪-1.2Δ₀ +3p‬‬

‫‪d9 t2g6 eg3‬‬ ‫‪1‬‬ ‫‪-0.6Δ₀‬‬ ‫‪d9 t2g6 eg3‬‬ ‫‪1‬‬ ‫‪-0.6Δ₀+3p‬‬

‫‪d10 t2g6 eg4‬‬ ‫‪0‬‬ ‫‪-oΔ₀+5p‬‬ ‫‪d10 t2g6 eg4‬‬ ‫‪0‬‬ ‫‪-oΔ₀+5p‬‬

‫ﻣﻥ ﺍﻟﺟﺩﻭﻝ ﻧﺟﺩ ﺃﻥ ﻓﻲ ﺍﻟﺗﻭﺯﻳﻌﺎﺕ ﺍﻻﻟﻛﺗﺭﻭﻧﻳﺔ ‪ d1 ,d2,d3,d8,d9,d10‬ﻣﺗﺳﺎﻭﻳﺔ ﻓﻲ ﻛﻼً ﻣﻥ ﺍﻟﻣﺟﺎﻝ ﺍﻟﺿﻌﻳﻑ ﻭ ﺍﻟﻣﺟﺎﻝ‬
‫ﺍﻟﻘﻭﻱ ﺑﻐﺽ ﺍﻟﻧﻅﺭ ﻋﻥ ﻗﻳﻣﺔ ‪. Δ‬ﺃﻣﺎ ﺑﺎﻟﻧﺳﺑﺔ ﻟﻠﺗﻭﺯﻳﻊ ﻣﻥ ‪ d4‬ﺇﻟﻰ ‪ d7‬ﻓﺄﻧﻧﺎ ﻧﺳﺗﺧﺩﻡ ﻗﻳﻣﺔ ‪ CFSE‬ﺑﺎﻹﺿﺎﻓﺔ ﺇﻟﻰ ﻗﻳﻣﺔ ﻁﺎﻗﺔ‬

‫ﺍﻻﺯﺩﻭﺍﺝ )‪ (P‬ﻟﻛﻲ ﻳﺗﻡ ﺗﻭﻗﻊ ﺍﻟﻣﻌﻘﺩ ﻣﻥ ﺍﻟﻧﻭﻉ ﺑﺭﻡ ﻋﺎﻟﻲ )‪ (High spin‬ﺃﻭ ﺑﺭﻡ ﻭﺍﻁﺊ )‪.(Low spin‬‬

‫ﻣﺛـــــﺎﻝ ‪ -:‬ﺃﻥ ﻗﻳﻣﺔ ‪ Δ₀‬ﻟﻼﻳﻭﻥ ‪ [Cr(H2O)6]3+‬ﺗﺳﺎﻭﻱ ‪، 17400 cm-1‬ﻣﺎﻫﻲ ﻁﺎﻗﺔ ﺍﺳﺗﻘﺭﺍﺭ ﺍﻟﻣﺟﺎﻝ ﺍﻟﺑﻠﻭﺭﻱ ﻟﻬﺫﺍ ﺍﻻﻳﻭﻥ‬

‫ﺍﻳﻭﻥ ‪ Cr3+‬ﻳﺗﺧﺫ ﺍﻟﺗﺭﻛﻳﺏ ﺍﻻﻟﻛﺗﺭﻭﻧﻲ ‪ (t2g)3‬ﻭﻁﺎﻗﺔ ﺍﺳﺗﻘﺭﺍﺭ ﺍﻟﻣﺟﺎﻝ ﺍﻟﺑﻠﻭﺭﻱ ﺑﻭﺣﺩﺓ ‪ Δ₀‬ﻫﻲ‪3 x -0.4Δ₀= -1.2Δ₀ :‬‬

‫‪-1.2 x 17400 = -20880 cm-1‬‬ ‫ﻭﻁﺎﻗﺔ )‪ (CFSE‬ﺑﻭﺣﺩﺓ ‪ cm-1‬ﻫﻲ‪:‬‬

‫ﻣﺛــــــــــــﺎﻝ ‪ -:‬ﻟﺩﻳﻙ ﺍﻟﻘﻳﻡ ‪ .P = 28000 cm-1 ، 2100 cm-1= Δ₀‬ﻟﻠﻣﻌﻘﺩ ‪ [Mn(H2O)6]3+‬ﺑﻳﻥ ﻫﻝ ﺍﻟﻣﻌﻘﺩ ﻋﺎﻟﻲ ﺍﻟﺑﺭﻡ‬
‫)‪ (High spin‬ﺍﻡ ﻭﺍﻁﺊ ﺍﻟﺑﺭﻡ )‪ (Low spin‬؟‬

‫‪Mn 25= [Ar] 4S2 3d5‬‬ ‫ﺍﻟﺣﻝ‪Mn3+=[Ar]4S03d4 :‬‬

‫ﺗﺗﻭﺯﻉ ‪ d4‬ﻛﻣﺎ ﻳﻠﻲ‬

‫‪27‬‬

‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫‪High Spin‬‬ ‫‪Low Spin‬‬
‫‪Weak field‬‬ ‫‪Strong field CFSE = -16Dq + p‬‬
‫‪CFSE= -6Dq‬‬ ‫‪= -16 x 2100 + 28000‬‬
‫‪= -6 x 2100= - 12600 cm-1‬‬ ‫‪= -5600 cm-1‬‬
‫ﻻ ﻳﻭﺟﺩ ﺍﺯﺩﻭﺍﺝ ﻟﻼﻟﻛﺗﺭﻭﻧﺎﺕ ﻻﻥ ﺍﻟﻔﺭﻕ ﺑﻳﻥ ﻁﺎﻗﺔ ﺍﻟﻣﺟﺎﻝ ﺍﻟﻘﻭﻱ ﻭ ﺍﻟﺿﻌﻳﻑ ﻣﺳﺎﻭﻳﺔ ﺍﻟﻰ )‪. (-7000 cm-1‬ﺃﻱ ﺃﻥ ﺍﻟﻣﻌﻘﺩ‬

‫ﻳﻔﺿﻝ ﺍﻟﺗﻭﺍﺟﺩ ﺑﺣﺎﻟﺔ ﺍﻟﺑﺭﻡ ﺍﻟﻌﺎﻟﻲ ‪.‬‬

‫ﻧﺳﺗﻧﺗﺞ ﻣﻥ ﺍﻟﻣﻼﺣﻅﺎﺕ ﻭﺍﻟﺟﺩﻭﻝ ﺃﻋﻼﻩ ﺃﻥ ‪:‬‬

‫• ﺇﻥ ﺍﻧﻔﺻﺎﻡ ﺍﻟﻣﺟﺎﻝ ﺍﻟﺑﻠﻭﺭﻱ ﻳﻘﻭﺩ ﺍﻟﻰ ﻣﻌﺭﻓﺔ ﺍﻟﺧﻭﺍﺹ ﺍﻟﻣﻐﻧﺎﻁﻳﺳﻳﺔ)ﻣﻌﻘﺩﺍﺕ ﻋﺎﻟﻳﺔ ﺍﻟﺑﺭﻡ ﻭ ﻣﻌﻘﺩﺍﺕ ﺍﻟﻭﺍﻁﺋﺔ ﺍﻟﺑﺭﻡ (‪.‬‬
‫• ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﻌﺎﻟﻳﺔ ﺍﻟﺑﺭﻡ)‪ (high spin‬ﻫﻲ ﺫﺍﺕ ﺧﻭﺍﺹ ﺑﺎﺭﺍﻣﻐﻧﺎﻁﻳﺳﻳﺔ ﻭ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﻭﺍﻁﺋﺔ ﺍﻟﺑﺭﻡ )‪ (low spin‬ﺫﺍﺕ‬

‫ﺧﻭﺍﺹ ﺩﺍﻳﺎﻣﻐﻧﺎﻁﻳﺳﻳﺔ ‪.‬‬

‫‪ ‬ﺗﺄﺛﻳﺭﺍﻟﻣﺟﺎﻝ ﺍﻟﻠﻳﻛﺎﻧﺩﻱ ﻟﻠﻣﻌﻘﺩﺍﺕ ﺍﻟﺭﺑﺎﻋﻳﺔ ﺍﻟﺳﻁﻭﺡ ‪-:‬‬
‫‪Splitting of d orbitals in Tetrahedral Complexes‬‬

‫ﺃﺣﺩ ﺍﻻﺷﻛﺎﻝ ﺍﻟﻬﻧﺩﺳﻳﺔ ﺍﻟﺗﻲ ﺗﺗﺧﺫﻫﺎ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺫﺍﺕ ﺍﻟﺗﻧﺎﺳﻕ ﺍﻟﺭﺑﺎﻋﻲ ﻫﻭ ﺷﻛﻝ ﺭﺑﺎﻋﻲ ﺍﻟﺳﻁﻭﺡ ﻭﻓﻲ ﻫﺫﺍ ﺍﻟﺗﺭﺗﻳﺏ ﺗﻛﻭﻥ‬
‫ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻗﺭﺏ ﻻﻭﺭﺑﻳﺗﺎﻻﺕ ‪ t2g‬ﻣﻧﻬﺎ ﻻﻭﺭﺑﻳﺗﺎﻻﺕ ‪ eg‬ﻭ ﺑﺫﻟﻙ ﻓﺄﻥ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ t2g‬ﺳﻭﻑ ﺗﻌﺎﻧﻲ ﺗﻧﺎﻓﺭﺍً ﺍﺷﺩ ﻣﻣﺎ ﺗﻌﺎﻧﻳﻪ‬
‫ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ eg‬ﻭ ﺑﺎﻟﺗﺎﻟﻲ ﺳﺗﺭﺗﻔﻊ ﺍﻟﻁﺎﻗﺔ ﻻﻭﺭﺑﻳﺗﺎﻻﺕ ‪ t2g‬ﻋﻠﻰ ﻋﻛﺱ ﻣﺎﻫﻭ ﻋﻠﻳﻪ ﻓﻲ ﺣﺎﻟﺔ ﺛﻣﺎﻧﻲ ﺍﻟﺳﻁﻭﺡ ‪،‬ﻭ ﻟﻛﻥ ﻟﻭﺟﻭﺩ‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﻋﺩﺩ ﺃﻗﻝ ﻣﻥ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﻟﺫﻟﻙ ﻓﺄﻥ ﻁﺎﻗﺔ ﺍﻻﻧﻔﺻﺎﻡ ﻓﻲ ﺣﺎﻟﺔ ﺭﺑﺎﻋﻲ ﺍﻟﺳﻁﻭﺡ ﺗﻛﻭﻥ ﺍﻗﻝ ﻣﻣﺎ ﻫﻭ ﻋﻠﻳﻪ ﻓﻲ ﺣﺎﻟﺔ ﺛﻣﺎﻧﻲ ﺍﻟﺳﻁﻭﺡ‬

‫ﻟﻸﺳﺑﺎﺏ ﺍﻟﺗﺎﻟﻳﺔ‪ :‬ﺃﻭﻻ‪ :‬ﻧﻅﺭﺍ ﻟﻭﺟﻭﺩ ﺃﺭﺑﻌﺔ ﻟﻳﻛﺎﻧﺩﺍﺕ ﺑﺩﻻً ﻣﻥ ﺳﺗﺔ ‪ ،‬ﺛﺎﻧﻳﺎً‪ :‬ﺃﻥ ﺃﻭﺭﺑﻳﺗﺎﻻﺕ ‪ d‬ﻻﺗﺗﻛﻳﻑ ﺑﺻﻭﺭﺓ ﺟﻳﺩﺓ ﻣﻊ‬

‫ﺍﻟﺗﻧﺎﻅﺭ ﺍﻟﺭﺑﺎﻋﻲ ﺍﻟﺳﻁﻭﺡ ‪ ،‬ﻭ ﻫﻛﺫﺍ ﻓﺈﻥ ﺍﻹﻧﻘﺳﺎﻡ ﻓﻲ ﺭﺑﺎﻋﻲ ﺍﻷﻭﺟﻪ ‪ Δt‬ﺳﻭﻑ ﻳﺳﺎﻭﻱ ﺗﻘﺭﻳﺑﺎ ‪ 4/9‬ﺍﻻﻧﻘﺳﺎﻡ ﺍﻟﻣﻭﺟﻭﺩ ﻓﻲ‬

‫‪Δt = 4/9 Δ₀‬‬ ‫ﺛﻣﺎﻧﻲ ﺍﻷﻭﺟﻪ ‪ ، Δo‬ﻭ ﺫﻟﻙ ﻋﻧﺩ ﺛﺑﺎﺕ ﺑﻘﻳﺔ ﺍﻟﻌﻭﺍﻣﻝ‪.‬‬

‫‪.‬‬

‫ﻭ ﻧﻅﺭﺍ ﻷﻥ ﻗﻳﻣﺔ ‪ Δt‬ﻓﻲ ﺭﺑﺎﻋﻲ ﺍﻷﻭﺟﻪ ﺩﺍﺋﻣﺎ ﺃﺻﻐﺭ ﻣﻥ ‪ Δo‬ﻓﻲ ﺛﻣﺎﻧﻲ ﺍﻷﻭﺟﻪ ‪ ،‬ﻓﺎﻟﻣﻌﻘﺩﺍﺕ ﺭﺑﺎﻋﻳﺔ ﺍﻷﻭﺟﻪ ﺩﺍﺋﻣﺎ ﻣﺎ‬
‫ﺗﻔﺿﻝ ﻋﺩﻡ ﺍﺯﺩﻭﺍﺝ ﺍﻹﻟﻛﺗﺭﻭﻧﺎﺕ ﻭ ﻳﻌﻁﻲ ﻣﻌﻘﺩﺍﺕ ﺑﺭﻡ ﻋﺎﻟﻲ )‪ (High spin‬ﻣﻊ ﺟﻣﻳﻊ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺳﻭﺍء ﻛﺎﻧﺕ ﻗﻭﻳﺔ ﺃﻭ‬
‫ﺿﻌﻳﻔﺔ ‪ ،‬ﺣﻳﺙ ﺗﻛﻭﻥ ﻁﺎﻗﺔ ﺍﻻﺯﺩﻭﺍﺝ ﺃﻛﺑﺭ ﻣﻥ ﻗﻳﻣﺔ ﻁﺎﻗﺔ ﺍﻟﻣﺟﺎﻝ ﺍﻟﺑﻠﻭﺭﻱ )‪ .(p > Δo‬ﻛﻣﺎ ﻧﺟﺩ ﺃﻥ ﻗﻳﻣﺔ ‪ CFSE‬ﻓﻲ‬
‫ﺛﻣﺎﻧﻲ ﺍﻷﻭﺟﻪ ﺳﻭﻑ ﺗﻛﻭﻥ ﺃﻛﺑﺭ ﻣﻥ ﻗﻳﻣﺔ ‪ CFSE‬ﻓﻲ ﺭﺑﺎﻋﻲ ﺍﻷﻭﺟﻪ ‪ .‬ﻭﻣﻥ ﻣﻘﺎﺭﻧﺔ ﻗﻳﻡ ‪ CFSE‬ﻓﻲ ﻛﻝ ﻣﻥ ﺭﺑﺎﻋﻲ‬
‫ﺍﻟﺳﻁﻭﺡ ﻭ ﺛﻣﺎﻧﻲ ﺍﻟﺳﻁﻭﺡ ﻓﻲ ﺟﺩﻭﻝ ﺃﺩﻧﺎﻩ ‪ ،‬ﻓﺈﻧﻪ ﻳﺗﺑﻳﻥ ﺑﺄﻥ ﺍﻟﺗﺭﺗﻳﺑﺎﺕ ‪ d0 , d5 , d10‬ﺳﻭﻑ ﺗﺳﺎﻭﻱ ﺻﻔﺭﺍ ﻓﻲ ﻛﻝ ﻣﻥ‬

‫ﺍﻟﻣﻌﻘﺩﺍﺕ ﺭﺑﺎﻋﻳﺔ ﺍﻟﺳﻁﻭﺡ ﻭ ﺛﻣﺎﻧﻲ ﺍﻟﺳﻁﻭﺡ‪.‬‬

‫ﻭﻳﻼﺣﻅ ﻓﻲ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﺭﺑﺎﻋﻳﺔ ﺍﻟﺳﻁﻭﺡ ﺇﻥ ﺍﻋﻠﻲ ﺍﺳﺗﻘﺭﺍﺭﻳﺔ ﻳﺿﻔﻳﻬﺎ ﺍﻟﻣﺟﺎﻝ ﺍﻟﻠﻳـــــﻛﺎﻧﺩﻱ ﻫﻲ ﻓﻲ ﻧﻅـــــــــــــــــﺎﻣﻲ‬
‫)‪ d2,d7(high spin‬ﻭﻟﻬﺫﺍ ﺍﻟﺳﺑﺏ ﻳﺗﺧﺫ ﻧﻅﺎﻡ ‪ d2‬ﺃﻭ‪ d7‬ﺍﻟﺷﻛﻝ ﺍﻟﻣﻧﺗﻅﻡ ﻟﺭﺑﺎﻋﻲ ﺍﻟﺳﻁﻭﺡ‪ .‬اﻟﺠدوﻝ اﻟﺘﺎﻟﻲ ﻴوﻀﺢ ﻗﻴﻤﺔ‬

‫)‪ (CFSE‬ﻟﻠﺘﺸﻛﻴﻝ )‪-:(dn‬‬

‫‪Dn High spin (HS) Low spin (LS) Tetrahedral‬‬
‫‪D‬‬ ‫‪Octahedral‬‬ ‫‪Octahedral‬‬ ‫‪Complexes‬‬

‫‪d1 -0.4‬‬ ‫‪-o.4 -0.6‬‬
‫‪d2 -0.8‬‬ ‫‪-0.8 -1.2‬‬
‫‪d3 -1.2‬‬ ‫‪-1.2 -0.8‬‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫‪d4 -o.6‬‬ ‫‪-1.6 -o.4‬‬

‫‪d5 0‬‬ ‫‪-2.0 0‬‬

‫‪d6 -0.4‬‬ ‫‪-2.4 -0.6‬‬

‫‪d7 -0.8‬‬ ‫‪-1.8 -1.2‬‬

‫‪d8 -1.2‬‬ ‫‪-1.2 -0.8‬‬

‫‪d9 -0.6‬‬ ‫‪-0.6 -0.4‬‬

‫‪d10 0‬‬ ‫‪00‬‬

‫ﻟﻭﺣﻅ ﺗﺟﺭﻳﺑﻳﺎً ﺃﻥ ﺍﻳﻭﻧﻲ ‪ d3‬ﻭ ‪ (Cr3+, Ni2+) d8‬ﻳﻔﺿﻼﻥ ﺇﻟﻰ ﺣﺩ ﻛﺑﻳﺭ ﺍﻟﺗﻧﺎﻅﺭ ﺍﻟﺛﻣﺎﻧﻲ ﺍﻟﺳﻁﻭﺡ ‪ ،‬ﺃﻣﺎ ﺃﻳﻭﻥ ‪(Co2+) d7‬‬

‫ﺍﻟﺫﻱ ﻳﺗﺧﺫ ﺃﺣﻳﺎﻧﺎ ﺍﻟﺗﻧﺎﻅﺭ ﺍﻟﺭﺑﺎﻋﻲ ﺍﻟﺳﻁﻭﺡ‪.‬‬

‫ﺍﻟﺗﺷﻭﻩ ﺍﻟﺭﺑﺎﻋﻲ ﻓﻲ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺛﻣﺎﻧﻳﺔ ﺍﻟﺳﻁﻭﺡ )ﺗﺷﻭﻩ ﺟﺎﻥ ‪ :‬ﺗﻳﻠﺭ( ‪:‬‬

‫ﺍﻟﺗﺷﻭﻩ ﻳﻘﺻﺩ ﺑﻪ ﺗﺣﻭﻝ ﺍﻟﺷﻛﻝ ﺍﻟﻔﺭﺍﻏﻲ ﻟﻠﻣﻌﻘﺩ ﺍﻟﺛﻣﺎﻧﻲ ﺍﻟﺳﻁﻭﺡ ﺍﻟﻣﻧﺗﻅﻡ ﺍﻟﻣﺗﻧﺎﻅﺭ ﺇﻟﻰ ﺷﻛﻝ ﺛﻧﺎﺋﻲ ﺍﻟﻬﺭﻡ ﺃﻟﻣﺭﺑﻌﻲ ﺍﻷﻗﻝ‬
‫ﺗﻧﺎﻅﺭﺍً ﺑﺗﺣﺭﻙ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﻓﻲ ﻭﺿﻊ ﺗﺭﺍﻧﺱ ‪ ،‬ﺍﻟﺷﻛﻝ ﺍﻟﺛﻣﺎﻧﻲ ﺍﻟﺳﻁﻭﺡ ﻫﻭ ﺍﻟﻣﻔﺿﻝ ﺑﺎﻟﻧﺳﺑﺔ ﺇﻟﻰ ﺍﻳﻭﻥ ﻓﻠﺯﻱ ﻣﻭﺟﺏ ﻣﺣﺎﻁ‬

‫ﺑﺳﺕ ﺷﺣﻧﺎﺕ ﺳﺎﻟﺑﺔ ﻟﻛﻥ ﺇﺫﺍ ﺃﺧﺗﻠﻑ ﺍﻟﺗﻭﺯﻳﻊ ﻟﻬﺫﻩ ﺍﻟﺷﺣﻧﺎﺕ ﺑﺳﺑﺏ ﺍﻟﺗﺭﺗﻳﺏ ﺍﻻﻟﻛﺗﺭﻭﻧﻲ ﺍﻟﻐﻳﺭ ﻣﺗﻣﺎﺛﻝ ﻟﺑﻌﺽ ﺍﻳﻭﻧﺎﺕ ﺍﻟﻔﻠﺯﺍﺕ‬
‫ﻓﻳﺻﺑﺢ ﺍﻟﺷﻛﻝ ﺍﻟﺛﻣﺎﻧﻲ ﻏﻳﺭ ﻣﺳﺗﻘﺭ ﻭﻧﻅﺭﻳﺔ ﺟﺎﻥ – ﺗﻳﻠﻠﺭ ﺗﻌﺎﻟﺞ ﻫﺫﻩ ﺍﻟﺗﻐﻳﺭﺍﺕ ‪.‬ﻟﺗﻭﺿﻳﺢ ﺫﻟﻙ ﻧﺄﺧﺫ ﻣﺛﺎﻝ ﺃﻳﻭﻥ ﺍﻟﻧﺣﺎﺱ ﺍﻟﺛﻧﺎﺋﻲ‬

‫)‪ (d9‬ﻭﺗﺗﻭﺯﻉ ﺍﻻﻟﻛﺗﺭﻭﻧﺎﺕ ﺑﺎﻟﺻﻳﻐﺔ ‪(t2g)6 (eg)3‬ﻓﻳﻛﻭﻥ ﺍﻟﺗﻭﺯﻳﻊ ﺑﺎﺣﺗﻣﺎﻟﻳﻥ ‪:‬‬

‫)‪(dz2)1(dx2-y2)2 (B‬‬ ‫)‪(dz2)2(dx2-y2)1 (A‬‬

‫ﻓﻔﻲ ﺍﻟﺻﻳﻐﺔ )‪ (A‬ﺃﻭﺭﺑﻳﺗﺎﻝ )‪(dx2-y2‬ﻳﻛﻭﻥ ﻏﻳﺭ ﻣﻣﺗﻠﺊ ‪ ،‬ﻓﺄﻥ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﻓﻲ ﺍﻟﻣﺳﺗﻭﻱ ‪ xy‬ﺗﻧﺟﺫﺏ ﻧﺣﻭ ﻧﻭﺍﺓ ﺍﻟﻧﺣﺎﺱ ﺑﺷﺩﺓ‬
‫ﺃﻗﻭﻯ ﻣﻥ ﺍﻧﺟﺫﺍﺏ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﻣﻭﺟﻭﺩﺓ ﻋﻠﻰ ﺍﻣﺗﺩﺍﺩ ﺇﺣﺩﺍﺛﻲ ‪، Z‬ﻭﻧﺗﻳﺟﺔ ﻟﻬﺫﺍ ﺍﻟﺗﺟﺎﺫﺏ ﻏﻳﺭ ﺍﻟﻣﺗﻛﺎﻓﺊ ﺗﻛﻭﻥ ﺍﻟﻣﺳﺎﻓﺔ ﺑﻳﻥ ﻓﻠﺯ –‬
‫ﻟﻳﻛﺎﻧﺩ ﻓﻲ ﺍﻟﻣﺳﺗﻭﻱ ‪ XY‬ﺍﻗﺻﺭ ﻣﻥ ﺍﻟﻣﺳﺎﻓﺔ ﺑﻳﻥ ﻓﻠﺯ‪ -‬ﻟﻳﻛﺎﻧﺩ ﻋﻠﻰ ﺍﻟﻣﺣﻭﺭ ‪ Z‬ﻭﻳﻌﻧﻲ ﺫﻟﻙ ﻭﺟﻭﺩ ﺃﺭﺑﻌﺔ ﺃﻭﺍﺻﺭ ﻗﺻﻳﺭﺓ ﻓﻲ‬
‫ﻣﺳﺗﻭﻱ ‪ XY‬ﻭﺍﺻﺭﺗﻳﻥ ﻁﻭﻳﻠﺗﻳﻥ ﻋﻠﻰ ﺍﻣﺗﺩﺍﺩ ﺍﻟﻣﺣﻭﺭ ‪ ،Z‬ﻭﻫﺫﺍ ﻳﻣﺛﻝ ﺷﻛﻝ ﺛﻣﺎﻧﻲ ﺍﻟﺳﻁﻭﺡ ﻣﻧﺣﺭﻑ ‪ ، distorted‬ﻭﺇﻁﺎﻟﺔ‬

‫ﺍﻷﻭﺍﺻﺭ ﺇﻟﻰ ﻣﺎﻻ ﻧﻬﺎﻳﺔ ﻳﺅﺩﻱ ﺇﻟﻰ ﺗﻛﻭﻳﻥ ﺍﻟﺷﻛﻝ ﺍﻟﺭﺑﺎﻋﻲ ﺍﻟﻣﺭﺑﻊ ﺍﻟﻣﺳﺗﻭﻱ ‪.square planer‬‬

‫ﺣﻳﺙ ﻳﻅﻬﺭ ﺍﻟﺗﺭﺗﻳﺏ ﺍﻟﻣﻣﺎﺛﻝ ﻓﻲ ﻣﺭﻛﺑﺎﺕ ﺍﻻﻳﻭﻧﺎﺕ ﺍﻻﺗﻳﺔ‪:‬‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫‪Electronic configuration t2g‬‬ ‫‪eg‬‬ ‫‪Examples‬‬

‫‪high spin d4‬‬ ‫‪(t2g)3 (eg)1‬‬ ‫)‪Cr(II).Mn(III‬‬

‫‪low spin d7‬‬ ‫‪(t2g)6 (eg)1‬‬ ‫)‪Co(II).Ni(III‬‬
‫‪d9‬‬ ‫‪(t2g)6 ( (e)g)3‬‬ ‫)‪Cu(II),Ag(II‬‬

‫ﻭ ﻟﻭ ﻛﺎﻥ ﺗﺭﺗﻳﺏ ﺇﻟﻳﻛﺗﺭﻭﻧﺎﺕ ﺍﻟﻣﺩﺍﺭ ‪ d‬ﻣﺗﻣﺎﺛﻼ ﺑﺎﻟﻧﺳﺑﺔ ﻟﻣﺟﺎﻝ ﺍﻟﻠﻳﻛﺎﻧﺩ ﺛﻣﺎﻧﻲ ﺍﻷﻭﺟﻪ ﻓﺈﻧﻬﺎ ﺳﻭﻑ ﺗﺗﻧﺎﻓﺭ ﻣﻊ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﺳﺗﺔ‬

‫ﺑﺎﻟﺗﺳﺎﻭﻱ‪ ،‬ﻭ ﻋﻠﻳﻪ ﻓﺈﻧﻪ ﺳﻭﻑ ﻳﺗﻛﻭﻥ ﺷﻛﻝ ﺛﻣﺎﻧﻲ ﺍﻟﺳﻁﻭﺡ ﻣﻧﺗﻅﻡ‪ .‬ﺣﻳﺙ ﻳﻅﻬﺭ ﺍﻟﺗﺭﺗﻳﺏ ﺍﻟﻣﺗﻣﺎﺛﻝ ﻓﻲ ﺍﻟﺗﺭﺗﻳﺑﺎﺕ ﺍﻻﻟﻛﺗﺭﻭﻧﻳﺔ‬

‫ﺍﻟﺗﺎﻟﻳﺔ ‪:‬‬

‫‪Electronic‬‬ ‫‪t2g eg‬‬ ‫‪Nature of ligand‬‬ ‫‪Examples‬‬
‫‪configuration‬‬ ‫‪field‬‬ ‫‪TiIVO2 , [Ti IV F6]2-‬‬
‫)‪(t2g)3 (eg‬‬
‫‪d0‬‬ ‫‪(t2g)3 (eg)2‬‬ ‫‪Strong or weak‬‬
‫)‪(t2g)6 (eg‬‬
‫‪d3‬‬ ‫‪(t2g)6 (eg)2‬‬ ‫‪Strong or weak [CrIII(oxalate)3]3-,[Cr(H2O)6]3+‬‬
‫‪(t2g)6 (eg)4‬‬
‫‪d5‬‬ ‫‪Weak‬‬ ‫‪[MnIIF6]4- , [FeIIIF6]3-‬‬

‫‪d6‬‬ ‫‪Strong‬‬ ‫‪[FeII(CN)6]4- , [Co(NH3)6]3+‬‬

‫‪d8‬‬ ‫‪Weak‬‬ ‫‪[NiIIF6]4- , [NiII(H2O)6]2+‬‬

‫‪d10‬‬ ‫‪Strong or weak‬‬ ‫‪[ZnII(NH3)6]2+ , [ZnII(H2O)6]2+‬‬

‫ﺇﻣﺎ ﺍﻟﺣﺎﻟﺔ )‪ (B‬ﻓﻬﻲ ﻋﻛﺱ ﺍﻟﺣﺎﻟﺔ )‪ (A‬ﻭﺃﻳﺿﺎ ﻧﺎﺩﺭﺓ ﺍﻟﺣﺩﻭﺙ‪.‬‬

‫ﺇﻣﺎ ﺍﻟﺗﺭﺗﻳﺏ ﺍﻟﻐﻳﺭ ﻣﺗﻣﺎﺛﻝ ﺍﻟﺣﺎﺻﻝ ﻓﻲ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ )‪ (t2g‬ﻳﻛﻭﻥ ﺍﻗﻝ ﺃﻫﻣﻳﺔ ﻭﻳﺳﺑﺏ ﺍﻧﺣﺭﺍﻓﺎً ﺍﺻﻐﺭ ﺑﻛﺛﻳﺭ ﻣﻥ ﺍﻻﻧﺣﺭﺍﻑ ﺍﻟﺫﻱ‬
‫ﻳﻌﺯﻯ ﻟﻠﺗﺭﺗﻳﺏ ﺍﻟﻐﻳﺭ ﻣﺗﻧﺎﻅﺭ ﻓﻲ ﺍﻭﺭﺑﺗﺎﻟﻲ )‪ (eg‬ﻭﺫﻟﻙ ﻷﻥ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ )‪ (t2g‬ﺍﻗﻝ ﺗﺄﺛﺭﺍً ﺑﺎﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﻣﺣﻳﻁﺔ ﻣﻥ ﺍﻭﺭﺑﻳﺗﺎﻟﻲ‬

‫)‪ (eg‬ﻭﺍﻟﺗﺭﻛﻳﺏ ﺍﻟﻐﻳﺭ ﻣﺗﻣﺎﺛﻝ ﻻﻭﺭﺑﻳﺗﺎﻻﺕ )‪ (t2g‬ﻧﺟﺩﻩ ﻓﻲ ‪:‬‬

‫‪Electronicconfiguration‬‬ ‫‪t2g‬‬ ‫‪eg‬‬ ‫‪Nature of Spin‬‬

‫‪d1‬‬ ‫‪(t2g)1‬‬ ‫)‪(eg‬‬ ‫‪High spin‬‬
‫‪d2‬‬ ‫‪(t2g)2‬‬ ‫)‪(eg‬‬ ‫‪High spin‬‬
‫‪d4‬‬ ‫‪(t2g)4‬‬ ‫)‪(eg‬‬ ‫‪Low spin‬‬

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‫‪d5‬‬ ‫)‪(t2g)5 (eg‬‬ ‫‪Low spin‬‬

‫‪d6‬‬ ‫‪(t2g)4 (eg)2‬‬ ‫‪High spin‬‬

‫‪d7‬‬ ‫‪(t2g)5 (eg)2‬‬ ‫‪High spin‬‬

‫ﻓﻲ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺫﺍﺕ ﺍﻟﺷﻛﻝ ﺛﻣﺎﻧﻲ ﺍﻷﻭﺟﻪ ﻓﺈﻥ ﺍﻟﺗﺷﻭﻫﺎﺕ ﺍﻟﻧﺎﺗﺟﺔ ﻣﻥ ﻣﺳﺗﻭﻳﺎﺕ ‪ t2g‬ﺳﻭﻑ ﺗﻛﻭﻥ ﺻﻐﻳﺭﺓ ﺟﺩﺍ ﻭ ﻻ ﻳﻣﻛﻥ‬
‫ﺍﻛﺗﺷﺎﻓﻬﺎ ‪ ،‬ﻭ ﻟﻛﻥ ﺍﻟﺗﺷﻭﻫﺎﺕ ﺍﻟﻧﺎﺗﺟﺔ ﻣﻥ ﺍﻻﻣﺗﻼء ﻏﻳﺭ ﺍﻟﻣﺗﺳﺎﻭﻱ ﻟﻣﺩﺍﺭﺍﺕ ‪ eg‬ﺫﺍﺕ ﺃﻫﻣﻳﺔ ﻛﺑﻳﺭﺓ‪.‬‬

‫ﺍﻟﻌﻭﺍﻣﻝ ﺍﻟﻣﺅﺛﺭﺓ ﻋﻠﻰ ﻗﻳﻣﺔ ‪: Δo‬‬

‫‪ (a‬ﺣﺎﻟﺔ ﺍﻷﻛﺳﺩﺓ ﻷﻳﻭﻥ ﺍﻟﻔﻠﺯ ‪Oxidation state .‬‬
‫ﺗﺯﺩﺍﺩ ﻗﻳﻣﺔ ‪ Δo‬ﻛﻠﻣﺎ ﺯﺍﺩ ﻋﺩﺩ ﺗﺄﻛﺳﺩ ﺍﻟﻔﻠﺯ ﻭ ﺻﻐﺭ ﻧﺻﻑ ﻗﻁﺭﻩ ‪ ،‬ﻭ ﻋﻠﻰ ﻫﺫﺍ ﻓﺈﻥ ﻗﻳﻣﺔ ‪ Δo‬ﻟﻠﻣﻌﻘﺩﺍﺕ ﺍﻟﻣﺣﺗﻭﻳﺔ ﻋﻠﻰ ‪M3+‬‬
‫ﺗﻛﻭﻥ ﺫﺍﺕ ﻗﻳﻣﺔ ﻣﺿﺎﻋﻔﺔ ﺗﻘﺭﻳﺑﺎ ﻟﻠﻘﻳﻣﺔ ﺍﻟﻣﻭﺟﻭﺩﺓ ﻓﻲ ﺣﺎﻟﺔ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﻣﺣﺗﻭﻳﺔ ﻋﻠﻰ ‪ ،، M2+‬ﻛﻣﺎ ﻳﺗﺿﺢ ﻣﻥ ﺍﻟﺳﻠﺳﻠﺔ‬

‫ﺍﻵﺗﻳﺔ‪:‬‬

‫< ‪– Mn2+ < Ni2+ < Co2+ < Fe2+ < V2+ < Fe3+ < Co3+ < Mn4+‬‬
‫‪Mo3+ < Rh3+ < Ru3+ < Pd4+ < Ir3+ < Pt4+‬‬

‫ﻓﺯﻳﺎﺩﺓ ﺍﻟﺷﺣﻧﺔ ﻋﻠﻰ ﺍﻷﻳﻭﻥ ﺍﻟﻔﻠﺯﻱ ﻳﻘﻠﻝ ﺣﺟﻡ ﺍﻷﻳﻭﻥ ﺍﻟﻔﻠﺯﻱ ﻭ ﻳﺅﺩﻱ ﺫﻟﻙ ﺍﻟﻰ ﺟﺫﺏ ﺍﻟﻠﻳﺟﺎﻧﺩﺍﺕ ﺃﻛﺛﺭ ﻭ ﺟﻌﻠﻬﺎ ﺃﻗﺭﺏ ﻣﻥ‬
‫ﻣﺩﺍﺭﺍﺕ ‪ d‬ﻟﻠﻔﻠﺯ‪ ،‬ﻣﻣﺎ ﻳﺯﻳﺩ ﻣﻥ ﻗﻭﺓ ﺍﻟﺗﻧﺎﻓﺭ ﺑﻳﻥ ﺍﻟﻠﻳﺟﺎﻧﺩﺍﺕ ﻭ ﺍﻟﻣﺩﺍﺭﺍﺕ ﺃﻛﺛﺭ‪ ،‬ﻭ ﻳﺟﻌﻝ ﺍﻟﻣﺩﺍﺭﺍﺕ ﺃﻛﺛﺭ ﺗﻬﻳﺟﺎ ﻭ ﺗﺯﺩﺍﺩ ﺑﺎﻟﺗﺎﻟﻲ‬

‫ﺩﺭﺟﺔ ﺍﻧﻘﺳﺎﻡ ﻣﺩﺍﺭﺍﺕ ‪. d‬‬

‫‪ - b‬ﻁﺑﻳﻌﺔ ﺍﻷﻳﻭﻥ ﺍﻟﻔﻠﺯﻱ‪:‬‬
‫ﻻ ﺗﺗﻐﻳﺭ ﻗﻳﻣﺔ ‪ Δo‬ﻛﺛﻳﺭﺍ ﺑﻳﻥ ﺃﻳﻭﻧﺎﺕ ﺍﻟﺳﻠﺳﺔ ﺍﻟﻭﺍﺣﺩﺓ ﺍﻟﺗﻲ ﻟﻬﺎ ﺣﺎﻟﺔ ﺗﺄﻛﺳﺩ ﻭﺍﺣﺩﺓ‪.‬‬

‫ﺑﻳﻧﻣﺎ ﺗﺯﺩﺍﺩ ﻗﻳﻣﺔ ‪ Δo‬ﻛﻠﻣﺎ ﺍﺗﺟﻬﻧﺎ ﺃﺳﻔﻝ ﺍﻟﻣﺟﻣﻭﻋﺔ ﻓﻲ ﺍﻟﻌﻧﺎﺻﺭ ﺍﻻﻧﺗﻘﺎﻟﻳﺔ ﻛﻣﺎ ﻳﻠﻲ‪:‬‬

‫)‪[Ir(NH3)6]3+ (41000 cm1-) > [Rh(NH3)6]3+ (34000 cm1-) > [Co(NH3)6]3+ (23000 cm1-‬‬

‫> ‪5 d6‬‬ ‫> ‪4d6‬‬ ‫‪3d6‬‬

‫ﺑﺣﻳﺙ ﻳﻛﻭﻥ ﺍﻻﺧﺗﻼﻑ ﻓﻘﻁ ﻓﻲ ﺭﻗﻡ ﺍﻟﻐﻼﻑ ﺍﻟﺭﺋﻳﺳﻲ‪ .‬ﻧﻼﺣﻅ ﺃﻥ ﺍﻟﻠﻳﻛﺎﻧﺩ ﻳﻛﻭﻥ ﻗﺭﻳﺏ ﻣﻥ ﺍﻟﻣﺩﺍﺭ ‪ 5d‬ﻷﻧﻪ ﺃﻛﺑﺭ ﻣﻥ ‪ 4d‬ﻭ‬
‫‪ ، 3d‬ﻓﻳﺻﺑﺢ ﺗﺄﺛﻳﺭﻩ ﺃﻛﺑﺭ ﻋﻠﻳﻪ ﻣﻣﺎ ﻳﺅﺩﻱ ﺇﻟﻰ ﻗﻭﺓ ﺗﻧﺎﻓﺭ ﺃﻋﻠﻰ ﻣﻊ ‪ 5d‬ﻭ ﻗﻳﻣﺔ ‪ Δo‬ﺗﺻﺑﺢ ﺃﻛﺑﺭ‪.‬‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﻭ ﻫﺫﺍ ﻳﻔﺳﺭ ﻅﻬﻭﺭ ﻣﻌﻘﺩﺍﺕ ﺫﺍﺕ ﺑﺭﻡ ﻭﺍﻁﺊ ‪ low spin‬ﺑﺩﻭﻥ ﺍﺳﺗﺛﻧﺎء ﺗﻘﺭﻳﺑﺎ ﻣﻊ ﻋﻧﺎﺻﺭ ﺍﻟﺳﻠﺳﻠﺔ ﺍﻟﺛﺎﻧﻳﺔ ﻭﺍﻟﺛﺎﻟﺛﺔ ‪ ،‬ﻣﻘﺎﺭﻧﺔ‬
‫ﻣﻊ ﻅﻬﻭﺭ ﻣﺭﻛﺑﺎﺕ ﻣﻌﻘﺩﺓ ﻣﻊ ﻋﻧﺎﺻﺭ ﺍﻟﺳﻠﺳﻠﺔ ﺍﻷﻭﻟﻰ ﺫﺍﺕ ﺍﻟﺑﺭﻡ ﺍﻟﻌﺎﻟﻲ ‪.high spin‬‬

‫‪ -c‬ﺍﻟﺷﻛﻝ ﺍﻟﻬﻧﺩﺳﻲ ﻟﻠﻣﻌﻘﺩ ‪.‬‬
‫ﻗﻳﻣﺔ ﺍﻧﻔﺻﺎﻡ ﺍﻟﻣﺟﺎﻝ ﺍﻟﺑﻠﻭﺭﻱ ﻓﻲ ﻣﻌﻘﺩﺍﺕ ﺭﺑﺎﻋﻲ ﺍﻟﺳﻁﻭﺡ ﺗﺳﺎﻭﻱ ‪ ، Δt = 4/9 Δoct.‬ﻓﻳﻛﻭﻥ ﺑﺎﻟﺗﺎﻟﻲ ﻗﻳﻣﺔ ‪ Δo‬ﻓﻲ ﺭﺑﺎﻋﻲ‬
‫ﺍﻟﺳﻁﻭﺡ ﺃﻗﻝ ﻣﻥ ﺛﻣﺎﻧﻲ ﺍﻟﺳﻁﻭﺡ ﻟﻧﻔﺱ ﺍﻟﻔﻠﺯ ﻭ ﻧﻔﺱ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﻣﺗﺻﻠﺔ ‪ ،‬ﻓﻭﺟﻭﺩ ﺃﺭﺑﻊ ﻟﻳﻛﺎﻧﺩﺍﺕ ﺑﺩﻻً ﻣﻥ ﺳﺗﺔ ﻓﻲ ﺍﻟﻣﻌﻘﺩﺍﺕ‬

‫ﺍﻟﺛﻣﺎﻧﻳﺔ ﺍﻟﺳﻁﻭﺡ ﻳﺅﺩﻱ ﺇﻟﻰ ﺍﻧﺧﻔﺎﺽ ﻓﻲ ﺍﻟﻣﺟﺎﻝ ﺍﻟﺑﻠﻭﺭﻱ ﻓﻲ ﺣﺎﻟﺔ ﺗﺳﺎﻭﻱ ﺍﻟﻌﻭﺍﻣﻝ ﺍﻷﺧﺭﻯ‪.‬‬

‫‪ -d‬ﻁﺑﻳﻌﺔ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ‪.‬‬

‫ﺗﺅﺛﺭ ﻁﺑﻳﻌﺔ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﻋﻠﻰ ﺩﺭﺟﺔ ﺍﻧﻘﺳﺎﻡ ﻣﺩﺍﺭﺍﺕ ‪ d‬ﻭ ﺑﺎﻟﺗﺎﻟﻲ ﻋﻠﻰ ﻗﻳﻡ ‪ Δo‬ﻭ ﺗﻅﻬﺭ ﺑﻭﺿﻭﺡ ﻓﻲ ﺃﻁﻳﺎﻑ ﺍﻻﻣﺗﺻﺎﺹ ‪.‬‬
‫ﻭﺑﺩﺭﺍﺳﺔ ﺍﻟﻁﻳﻑ ﺍﻻﻟﻛﺗﺭﻭﻧﻲ ﻟﺳﻠﺳﻠﺔ ﻛﺎﻣﻠﺔ ﻣﻥ ﻣﻌﻘﺩﺍﺕ ﺍﻟﻔﻠﺯ ﺍﻻﻧﺗﻘﺎﻟﻲ ﺳﺎﻋﺩﺕ ﻋﻠﻰ ﺇﻳﺟﺎﺩ ﻁﺎﻗﺔ ﺍﻻﻧﻔﺻﺎﻡ ‪ Δo‬ﻋﻣﻠﻳﺎً‪ ،‬ﻭ ُﻭﺟﺩ‬

‫ﺃﻥ ﻗﻳﻣﺔ ‪ Δo‬ﻷﻱ ﺃﻳﻭﻥ ﻓﻠﺯﻱ ﺍﻧﺗﻘﺎﻟﻲ ﺗﺧﺗﻠﻑ ﺣﺳﺏ ﺍﻟﻠﻳﻛﺎﻧﺩ ﺍﻟﻣﺗﺻﻝ ﺑﺎﻟﻔﻠﺯ ‪ ،‬ﻛﻣﺎ ﻳﺗﺿﺢ ﻓﻲ ﺍﻟﻣﺛﺎﻝ ﺍﻟﺗﺎﻟﻲ‪:‬‬

‫ﻭ ﺗﺳﻣﻰ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﺗﻲ ﺗﺳﺑﺏ ﺍﻧﻘﺳﺎﻣﺎ ﺿﺋﻳﻼ ﻟﻣﺳﺗﻭﻳﺎﺕ ﺍﻟﻣﺩﺍﺭ ‪ d‬ﺑﺎﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﺿﻌﻳﻔﺔ ؛ ﻓﻲ ﺣﻳﻥ ﺃﻥ ﺍﻟﺗﻲ ﺗﺣﺩﺙ‬
‫ﺍﻧﻘﺳﺎﻣﺎ ﻛﺑﻳﺭﺍ ﻳﻁﻠﻕ ﻋﻠﻳﻬﺎ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﻘﻭﻳﺔ‪ ،‬ﻭ ﻳﻣﻛﻥ ﺗﺭﺗﻳﺏ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﺷﺎﺋﻌﺔ ﻓﻲ ﺳﻠﺳﻠﺔ ﻋﻠﻰ ﺣﺳﺏ ﻗﻭﺗﻬﺎ ﺑﺎﻻﻋﺗﻣﺎﺩ‬

‫ﻋﻠﻰ ﺍﻟﻧﺗﺎﺋﺞ ﺍﻟﺗﺟﺭﻳﺑﻳﺔ ‪ ،‬ﻭﺗﺳﻣﻰ ﻫﺫﻩ ﺍﻟﺳﻠﺳﻠﺔ ﺑﺎﻟﺳﻠﺳﻠﺔ ﺍﻟﻁﻳﻔﻭﻛﻳﻣﻳﺎﺋﻳﺔ )‪ ،(Spectrochemical Series‬ﻭ ﻫﻲ ﻛﺎﻟﺗﺎﻟﻲ‪:‬‬

‫‪Increased Δ ,Strong Field‬‬
‫ﻭﺍﻟﺟﺩﻭﻝ ﺃﺩﻧﺎﻩ ﻳﺑﻳﻥ ﻗﻳﻡ ﺍﻧﻔﺻﺎﻡ ﺍﻟﻣﺟﺎﻝ ﺍﻟﺑﻠﻭﺭﻱ‪ Δ₀‬ﻟﺑﻌﺽ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﻔﻠﺯﻳﺔ ﺍﻟﺛﻣﺎﻧﻲ ﺍﻟﺳﻁﻭﺡ‪:‬‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫‪.‬‬

‫ﻣﺛﺎﻝ‪ :‬ﺭﺗﺏ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻻﺗﻳﺔ ﺣﺳﺏ ﺗﺳﻠﺳﻝ ﺃﺯﺩﻳﺎﺩ ﻗﻳﻣﺔ ‪[Cr(H2O)6]3+ ,[CrCI6]3- ,[CrF6]3- : Δ₀‬‬

‫ﺍﻟﺟﻭﺍﺏ‪ :‬ﻣﻥ ﻣﻼﺣﻅﺔ ﺍﻟﺳﻠﺳﻠﺔ ﺍﻟﻁﻳﻔﻭﻛﻳﻣﻳﺎﺋﻳﺔ ﻧﺟﺩ ﺃﻥ ﺍﻟﻣﺟﺎﻝ ﺍﻟﻠﻳﻛﺎﻧﺩﻱ ﻳﻘﻊ ﺣﺳﺏ ﺍﻟﺗﺳﻠﺳﻝ ‪ H2O > F- > Cl-‬ﻭﺑﺫﻟﻙ ﻓﺄﻥ‬
‫ﻗﻳﻣﺔ ‪ Δ₀‬ﺍﻟﻣﻌﻁﺎﺓ ﻓﻲ ﻫﺫﺍ ﺍﻟﻣﺛﺎﻝ ﺗﺗﺑﻊ ﻧﻔﺱ ﺍﻟﺗﺳﻠﺳﻝ ‪.‬‬

‫ﻣﺣﺎﺳﻥ ﻭ ﻋﻳﻭﺏ ﻧﻅﺭﻳﺔ ﺍﻟﻣﺟﺎﻝ ﺍﻟﺑﻠﻭﺭﻱ ‪:‬‬

‫‪ .A‬ﻗﺩﺭﺗﻬﺎ ﻋﻠﻰ ﺇﻋﻁﺎء ﻧﺗﺎﺋﺞ ﺟﻳﺩﺓ ﻓﻲ ﺗﻔﺳﻳﺭ ﺗﻛﻭﻥ ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ‪.‬‬
‫‪ .B‬ﻗﺩﺭﺗﻬﺎ ﻋﻠﻰ ﺗﻔﺳﻳﺭ ﺃﻁﻳﺎﻑ ﺍﻻﻣﺗﺻﺎﺹ‪.‬‬

‫‪ .C‬ﻗﺩﺭﺗﻬﺎ ﻋﻠﻰ ﺗﻔﺳﻳﺭ ﺗﻛﻭﻥ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﺑﺎﺭﺍ ﻣﻐﻧﺎﻁﻳﺳﻳﺔ ﻭ ﺍﻟﺩﺍﻳﺎ ﻣﻐﻧﺎﻁﻳﺳﻳﺔ‪.‬‬
‫‪ .D‬ﺃﻭﺟﺩﺕ ﺍﻟﺳﻠﺳﻠﺔ ﺍﻟﻁﻳﻔﻭﻛﻳﻣﻳﺎﺋﻳﺔ ﺍﻟﺗﻲ ﺍﺳﺗﻁﺎﻋﺕ ﺃﻥ ﺗﻭﺿﺢ ﺍﻟﻠﻳﺟﺎﻧﺩﺍﺕ ﺍﻟﻘﻭﻳﺔ ﻭ ﺍﻟﺿﻌﻳﻔﺔ ؛ ﻭ ﻟﻛﻧﻬﺎ ﻟﻡ ﺗﺳﺗﻁﻊ‬
‫ﺗﻔﺳﻳﺭ ﻫﺫﻩ ﺍﻟﺳﻠﺳﻠﺔ ﺑﻧﺎءﺍ ﻋﻠﻰ ﺍﻟﻣﻌﻠﻭﻣﺎﺕ ﺍﻟﻘﻳﺎﺳﻳﺔ ﺍﻟﻣﻌﺗﺎﺩﺓ ﻣﺛﻝ )ﺍﻟﺳﺎﻟﺑﻳﺔ ﺍﻟﻛﻬﺭﺑﻳﺔ ‪ ،‬ﺍﻟﺣﺟﻡ ‪ ،‬ﺍﻻﺳﺗﻘﻁﺎﺏ ‪،‬ﺍﻟﻌﺯﻡ‬
‫ﺍﻟﻘﻁﺑﻲ ( ﻓﻣﻥ ﺍﻟﻣﻔﺗﺭﺽ ﺑﻧﺎءﺍ ﻋﻠﻰ ﻓﺭﺿﻳﺔ ﺍﻟﻧﻅﺭﻳﺔ ﺃﻥ ﺗﻛﻭﻥ ﺍﻟﻠﻳﺟﺎﻧﺩﺍﺕ ﺍﻟﺳﺎﻟﺑﺔ ﺍﻟﺷﺣﻧﺔ ﺃﻛﺛﺭ ﻗﺩﺭﺓ ﻋﻠﻰ ﺇﺣﺩﺍﺙ‬

‫ﺍﻧﻔﺻﺎﻡ ﺍﻟﻣﺩﺍﺭﺍﺕ ‪ d‬ﺑﺳﺑﺏ ﺍﻟﺗﻧﺎﻓﺭ ﺍﻟﻧﺎﺷﺊ ﻣﻊ ﺇﻟﻛﺗﺭﻭﻧﺎﺕ ﺫﺭﺓ ﺍﻟﻌﻧﺻﺭ ﺍﻻﻧﺗﻘﺎﻟﻲ ﻛﻣﺎ ﻓﻲ ﻟﻳﻛﺎﻧﺩ ﺍﻳﻭﻥ ﺍﻟﻔﻠﻭﺭﻳﺩ‪.‬‬
‫‪ .E‬ﻣﻭﻗﻊ ﺧﻁﺄ ﺍﻟﻧﻅﺭﻳﺔ ﻳﻌﻭﺩ ﺇﻟﻰ ﻋﺩﻡ ﺍﻫﺗﻣﺎﻣﻬﺎ ﺑﺎﻟﺗﺄﺛﻳﺭﺍﺕ ﺍﻟﺗﺳﺎﻫﻣﻳﺔ ‪.‬‬

‫ﻭﺑﺎﻟﺗﺎﻟﻲ ﻓﺈﻥ ﺍﻟﻔﺭﺿﻳﺔ ﺍﻻﻟﻛﺗﺭﻭﺳﺗﺎﺗﻳﻛﻳﺔ ﺍﻟﻣﺳﺗﺧﺩﻣﺔ ﻓﻲ ﻫﺫﻩ ﺍﻟﻧﻅﺭﻳﺔ ﻭ ﺍﻋﺗﺑﺎﺭ ﺍﻟﻠﻳﻛﺎﻧﺩ ﻛﻧﻘﺎﻁ ﻣﺷﺣﻭﻧﺔ ﺗﺅﺛﺭ ﻋﻠﻰ‬
‫ﺃﻭﺭﺑﻳﺗﺎﻻﺕ ‪ d‬ﻟﻠﺫﺭﺓ ﺍﻟﻣﺭﻛﺯﻳﺔ ﻭ ﺗﺅﺩﻱ ﺇﻟﻰ ﺍﻧﻘﺳﺎﻣﻬﺎ ﻓﻘﻁ ؛ ﻭ ﻻ ﺗﻣﺗﺯﺝ ﺃﻭﺭﺑﻳﺗﺎﻻﺗﻬﺎ ﻣﻊ ﺃﻭﺭﺑﻳﺗﻼﺕ ﺍﻟﻠﻳﻛﺎﻧﺩ ﻭ ﻻ ﺗﺷﺗﺭﻙ‬
‫ﺍﻟﻛﺗﺭﻭﻧﺎﺗﻬﺎ ﻓﻲ ﺣﺩﻭﺙ ﺍﻷﺻﺭﺓ ﻭ ﺍﻟﺗﻲ ﺍﻋﺗﺑﺭﺗﻬﺎ ﻫﺫﻩ ﺍﻟﻧﻅﺭﻳﺔ ﺑﺄﻧﻬﺎ ﺭﺍﺑﻁﺔ ﺃﻳﻭﻧﻳﺔ( ﻻ ﻳﺗﻁﺎﺑﻕ ﻣﻊ ﺣﺎﻻﺕ ﻛﺛﻳﺭﺓ ؛ ﻧﻅﺭﺍ ﻟﻛﻭﻥ‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺗﻣﺗﻠﻙ ﺃﻭﺭﺑﻳﺗﺎﻻﺕ ﻛﺗﺭﻭﻧﺎﺕ ﻭ ﺣﺟﻭﻣﺎ ﻣﺧﺗﻠﻔﺔ ﻣﻘﺎﺭﻧﺔ ﻣﻊ ﺍﻟﺫﺭﺍﺕ ﺍﻟﻔﻠﺯﻳﺔ ﺗﺗﺩﺍﺧﻝ ﻣﻊ ﻣﺩﺍﺭﺍﺕ ﺍﻟﻔﻠﺯ ‪ ،‬ﺃﺩﻯ ﻛﻝ ﺫﻟﻙ‬
‫ﺇﻟﻰ ﻅﻬﻭﺭ ﻧﻅﺭﻳﺔ ﺍﻟﻣﺩﺍﺭ ﺍﻟﺟﺯﻳﺋﻲ‪.‬‬

‫ﻧﻅﺭﻳﺔ ﺍﻻﻭﺭﺑﻳﺗﺎﻝ ﺍﻟﺟﺯﻳﺋﻲ ﻟﻠﻣﻌﻘﺩﺍﺕ‪:‬‬
‫‪.Molecular Orbital Theory:‬‬

‫ﺇﻥ ﻧﻅﺭﻳﺔ ﺍﻻﻭﺭﺑﻳﺗﺎﻝ ﺍﻟﺟﺯﻳﺋﻲ ﺗﻌﻁﻲ ﻭﺻﻔﺎ ﺃﻛﺛﺭ ﺩﻗﺔ ﻟﻠﺗﺭﺍﺑﻁ ﺍﻟﻛﻳﻣﻳﺎﺋﻲ ﻓﻲ ﻣﻌﻘﺩﺍﺕ ﺍﻟﻌﻧﺎﺻﺭ ﺍﻻﻧﺗﻘﺎﻟﻳﺔ ‪.‬ﻓﻲ ﻫﺫﻩ ﺍﻟﻧﻅﺭﻳﺔ‬
‫ﻧﻧﺷﺊ ﺳﻠﺳﻠﺔ ﻣﻥ ﻣﺩﺍﺭﺍﺕ ﺟﺯﻳﺋﻳﺔ )ﻭ ﻫﻲ ﺍﻟﺗﻲ ﺗﻣﺛﻝ ﻣﺩﺍﺭﺍﺕ ﺍﻟﻣﻌﻘﺩ( ﻭ ﺫﻟﻙ ﺑﺎﺳﺗﺧﺩﺍﻡ ﻁﺭﻳﻘﺔ ﺍﻹﺗﺣﺎﺩ ﺍﻟﺧﻁﻲ ﻟﻠﻣﺩﺍﺭﺍﺕ ﻣﻥ‬

‫ﻣﺩﺍﺭﺍﺕ ﺫﺭﻳﺔ ﻋﻠﻰ ﺃﻳﻭﻥ ﺍﻟﻔﻠﺯ ﻭ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ )‪( Linear Compination of Atomic Orbitals LCAO‬‬

‫ﺇﻥ ﺃﻭﻝ ﻣﺎ ﻳﻧﺑﻐﻲ ﻣﻌﺭﻓﺗﻪ ﻋﻧﺩ ﺗﻁﺑﻳﻕ ﻧﻅﺭﻳﺔ ﺍﻷﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﺟﺯﻳﺋﻳﺔ ﻋﻠﻰ ﻧﻭﻉ ﻣﻌﻳﻥ ﻣﻥ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﻔﻠﺯﻳﺔ " ﻫﻭ ﺗﺣﺩﻳﺩ ﺃﻱ‬
‫ﺍﻷﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﺗﻲ ﻳﻣﻛﻧﻬﺎ ﺃﻥ ﺗﺗﺩﺍﺧﻝ ﻭ ﺃﻱ ﺍﻟﻣﺩﺍﺭﺍﺕ ﺍﻟﺗﻲ ﻻ ﻳﻣﻛﻧﻬﺎ ﺃﻥ ﺗﺗﺩﺍﺧﻝ "‪.‬‬

‫ﺑﺩﺍﻳ ُﺔ ﻳﺗﻡ ﺷﺭﺡ ﺗﺩﺍﺧﻝ ﺃﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﻔﻠﺯ ﻭ ﺍﻟﻠﻳﻛﺎﻧﺩ ﺍﻟﺗﻲ ﺗﻣﺗﻠﻙ ﺍﻟﺧﻭﺍﺹ ﺍﻟﻣﺗﻣﺎﺛﻠﺔ ﺗﺩﺍﺧﻼ ﺧﻁﻳﺎ )ﺗـﺂﺻﺭ ﻣﺣﻭﺭﻱ( ﻟﺗﻛﻭﻳﻥ‬
‫ﺃﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﺗﺭﺍﺑﻁ ‪ σ‬ﺍﻟﺗﺳﺎﻫﻣﻳﺔ )‪.(bonding molecular orbital‬‬

‫ﺍﻟﺗﺄﺻﺭ ‪ σ‬ﻓﻲ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﺛﻣﺎﻧﻳﺔ ﺍﻟﺳﻁﻭﺡ‪-:‬‬

‫ﻓﺈﺫﺍ ﺍﻋﺗﺑﺭﻧﺎ ﻣﻌﻘﺩ ﺛﻣﺎﻧﻲ ﺍﻟﺳﻁﻭﺡ )‪ ML6 (octahedral‬ﻭ ﺍﻓﺗﺭﺿﻧﺎ ﺑﺄﻥ ﺗﺭﺍﺑﻁ ‪ σ‬ﺳﻳﻛﻣﺎ ﻫﻭ ﺍﻟﻣﻬﻡ ﻓﻘﻁ )ﺣﻳﺙ ﻳﺣﺩﺙ‬
‫ﺍﻟﺗﺩﺍﺧﻝ ﺑﻳﻥ ﻣﺩﺍﺭﺍﺕ ﺍﻟﺗﻛﺎﻓﺅ ﺍﻟﺧﺎﺭﺟﻲ (‪.‬‬

‫ﻓﺈﻧﻧﺎ ﻧﺟﺩ ﺃﻥ ﻣﺩﺍﺭﺍﺕ ﻏﻼﻑ ﺗﻛﺎﻓﺅ ﺍﻟﻔﻠﺯ ﺍﻻﻧﺗﻘﺎﻟﻲ ﻓﻲ ﺍﻟﺳﻠﺳﻠﺔ ﺍﻷﻭﻟﻰ ﻫﻲ‪ 3d 4s 4p :‬ﻭ ﻫﻲ ﺗﺳﻌﺔ ﻣﺩﺍﺭﺍﺕ ؛ ﻭ ﻣﻥ ﺑﻳﻧﻬﺎ‬

‫ﻧﺟﺩ ﺃﻥ ﺳﺗﺎً ﻣﻧﻬﺎ ﻓﻘﻁ ﻟﻬﺎ ﻓﺻﻭﺹ ﺗﺗﺟﻪ ﻧﺣﻭ ﺃﺭﻛﺎﻥ ﺛﻣﺎﻧﻲ ﺍﻟﺳﻁﻭﺡ )ﻋﻠﻰ ﻁﻭﻝ ﺍﻟﺭﺍﺑﻁﺔ ‪ ( M-L‬ﻭ ﻫﻲ ﻣﺩﺍﺭﺍﺕ ﺫﺭﻳﺔ‬

‫ﻣﻧﺎﺳﺑﺔ ﻟﺗﻛﻭﻳﻥ ﺭﻭﺍﺑﻁ ﻣﻥ ﻧﻭﻉ ﺳﻳﺟﻣﺎ ﻭ ﻫﻲ ﻛﺎﻟﺗﺎﻟﻲ ‪ 4pz , 4py , 4px , 4s , 3dz2 , 3dx2-y2‬ﺣﻳﺙ ﻳﺭﻣﺯ ﻟﻬﺎ ﺣﺳﺏ‬

‫ﺭﻣﺯﻳﺔ ﺍﻟﺗﻧﺎﻅﺭ‬ ‫ﻧﻅﺭﻳﺔ ﺍﻟﻣﺟﻣﻭﻋﺔ )‪ (Group Theory‬ﻋﻠﻰ ﺍﻟﺗﻭﺍﻟﻲ‬
‫‪t1u‬‬ ‫ﺍﻻﻭﺭﺑﻳﺗﺎﻝ‬
‫)‪( 4pz , 4py , 4px‬‬

‫) ‪a1g (4s‬‬

‫) ‪eg (3dz2 , 3dx2-y2‬‬

‫)‪t2g (dxy,dyz,dxz‬‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﺃﻣﺎ ﺍﻷﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﺛﻼﺛﺔ ﺍﻷﺧﺭﻯ ﻭ ﻫﻲ ‪ (t2g) 3dxy , 3dxz , 3dzy‬ﻓﺈﻥ ﻓﺻﻭﺻﻬﺎ ﺗﻘﻊ ﺑﻳﻥ ﺍﻹﺣﺩﺍﺛﻳﺎﺕ ﺍﻟﺩﻳﻛﺎﺭﺗﻳﺔ ‪x,y,z‬‬
‫ﻭ ﺑﺎﻟﺗﺎﻟﻲ ﻓﻬﻲ ﻻ ﺗﻧﺎﺳﺏ ﻣﻥ ﺣﻳﺙ ﺷﻛﻠﻬﺎ ﺍﻟﺗﺭﺍﺑﻁ ﺳﻳﻛﻣﺎ ﻟﺫﻟﻙ ﻓﺄﻧﻬﺎ ﺗﻌﺩ ﻏﻳﺭ ﺁﺻﺭﻳﺔ )‪.(non-bonding‬‬

‫ﺃﻣﺎ ﻣﺩﺍﺭﺍﺕ ﻏﻼﻑ ﺗﻛﺎﻓﺅ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﻓﻬﻲ ﺗﺗﺭﻛﺏ ﻏﺎﻟﺑﺎ ﻓﻲ ﻣﻌﻅﻡ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﻣﻥ ﻣﺩﺍﺭﺍﺕ ‪ s , p , d‬ﻭ ﺗﻌﻁﻲ ﻣﺩﺍﺭﺍﺕ ﺫﺍﺕ‬
‫ﺗﻣﺎﺛﻝ ﻣﻣﺎﺛﻝ ﻟﻣﺩﺍﺭﺍﺕ ﺍﻟﻔﻠﺯ ﻟﺗﻛﻭﻳﻥ ﺭﻭﺍﺑﻁ ‪. σ‬‬

‫ﻭ ﻓﻳﻣﺎ ﻳﻠﻲ ﺃﺷﻛﺎﻝ ﺍﻻﺗﺣﺎﺩ ﺍﻟﺧﻁﻲ ﻟﻠﻣﺩﺍﺭﺍﺕ ﺍﻟﺫﺭﻳﺔ ‪:‬‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﺗﻔﺗﺭﺽ ﻧﻅﺭﻳﺔ ﺍﻷﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﺟﺯﻳﺋﻳﺔ ﺑﺻﻭﺭﺓ ﻋﺎﻣﺔ ﺃﻥ ﻟﻸﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﺟﺯﻳﺋﻳﺔ ﺍﻟﺭﺍﺑﻁﺔ ‪(bonding molecular‬‬
‫)‪ orbital‬ﻟﻬﺎ ﻁﺎﻗﺔ ﺃﻭﻁﺄ ﻣﻥ ﻁﺎﻗﺔ ﺍﻻﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﺗﻲ ﺃﺳﻬﻣﺕ ﻓﻲ ﺗﻛﻭﻳﻧﻬﺎ ﻭ ﺍﻟﻣﻌﺎﻛﺳﺔ ﻟﻼﺭﺗﺑﺎﻁ )‪molecular orbital‬‬

‫‪(antibonding‬ﻟﻬﺎ ﻁﺎﻗﺔ ﺍﻋﻠﻰ ﻣﻥ ﻁﺎﻗﺔ ﺍﻻﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﺗﻲ ﺃﺳﻬﻣﺕ ﻓﻲ ﺗﻛﻭﻳﻧﻬﺎ ‪ ،‬ﺇﻣﺎ ﺍﻻﻭﺭﺑﻳﺗﺎﻻﺕ ﻏﻳﺭ ﺍﻻﺻﺭﻳﺔ ﻟﻬﺎ ﻧﻔﺱ‬
‫ﻁﺎﻗﺔ ﺍﻻﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﻌﺎﺋﺩﺓ ﻟﻬﺎ ‪ ،‬ﻭ ﻳﻧﺗﺞ ﻋﻥ ﺫﻟﻙ ﻣﺎ ﻳﺳﻣﻰ ﺑﻣﺧﻁﻁ ﻣﺳﺗﻭﻯ ﺍﻟﻁﺎﻗﺔ )‪ (Energy level diagram‬ﺍﻟﻣﺗﻣﺛﻝ‬

‫ﺑﺎﻟﺷﻛﻝ ﺃﺩﻧﺎﻩ‪.‬‬

‫‪ .A‬ﺗﻣﻸ ﺍﻻﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﺗﺄﺻﺭﻳﺔ ) ﻭﻫﻲ ‪ (eg,t1u,a1g‬ﺑﺎﺛﻧﻲ ﻋﺷﺭ ﺇﻟﻛﺗﺭﻭﻥ )ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﺳﺗﺔ ( ﻟﺗﻛﻭﻳﻥ‬
‫ﺍﻷﻭﺍﺻﺭ ﺳﻛﻣﺎ ﻓﻲ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﺛﻣﺎﻧﻳﺔ ﺍﻟﺳﻁﻭﺡ‪.‬‬

‫‪ -B‬ﺃﻣﺎ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ﺍﻳﻭﻥ ﺍﻟﻔﻠﺯ ﺍﻟﺧﺎﺻﺔ ﺑﻪ ﻓﺗﺷﻐﻝ ﺍﻻﻭﺭﺑﻳﺗﺎﻻﺕ ﻏﻳﺭ ﺍﻻﺻﺭﻳﺔ )‪ (t2g‬ﻭﺇﺫﺍ ﺍﻗﺗﺿﻰ ﺍﻷﻣﺭ ﻳﻣﻸ ﺍﻻﻭﺭﺑﻳﺗﺎﻟﻳﻥ‬
‫)*‪. (eg‬ﻛﻣﺎ ﻓﻲ ﺍﻟﻣﺛﺎﻝ ﺍﻟﺗﺎﻟﻲ ‪:‬‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﻣﺛـــــــــﺎﻝ‪ :‬ﺑﺎﺳﺗﺧﺩﺍﻡ ﻧﻅﺭﻳﺔ ﺍﻻﻭﺭﺑﻳﺗﺎﻝ ﺍﻟﺟﺯﻳﺋﻲ ‪ ،‬ﺃﻛﺗﺏ ﺍﻟﺗﻭﺯﻳﻊ ﺍﻻﻟﻛﺗﺭﻭﻧﻲ ﻟﻣﻌﻘﺩ ﺳﺩﺍﺳﻲ ﻣﺎﺋﺎﺕ ﺍﻟﺗﻳﺗﺎﻧﻳﻭﻡ )‪(III‬‬
‫‪ . [Ti(H2O)6]3+‬ﺛﻡ ﺃﺫﻛﺭ ﻟﻣﺎﺫﺍ ﻳﻌﺗﺑﺭ ﺑﺎﺭﺍﻣﻐﻧﺎﻁﻳﺳﻲ ﻭ ﺑﻧﻔﺳﺟﻲ ﺍﻟﻠﻭﻥ ‪.‬‬

‫ﺍﻟﺣﻝ ‪:‬‬

‫‪Ti : [Ar]3d24s2‬‬
‫‪Ti3+ : [Ar]3d1‬‬
‫‪[Ti(H2O)6]3+: (a1g)2(t1u)6(eg)4(t2g)1(eg*)0‬‬

‫ﻣﻥ ﻓﺣﺹ ﺍﻟﺗﺭﻛﻳﺏ ﺍﻻﻟﻛﺗﺭﻭﻧﻲ ﻧﺟﺩ ﺃﻥ ﺍﻟﻣﻌﻘﺩ ﻳﺣﺗﻭﻱ ﻋﻠﻰ ﺍﻟﻛﺗﺭﻭﻥ ﻭﺍﺣﺩ ﻣﻧﻔﺭﺩ ؛ ﻓﻳﻛﻭﻥ ﺑﺎﺭﺍ ﻣﻐﻧﺎﻁﻳﺳﻲ ‪ .‬ﻭ ﺍﻟﻠﻭﻥ‬
‫ﺍﻟﺑﻧﻔﺳﺟﻲ ﻟﻠﻣﻌﻘﺩ ﻧﺗﻳﺟﺔ ﺍﻻﻧﺗﻘﺎﻝ ﺍﻹﻟﻛﺗﺭﻭﻧﻲ *‪ t2g→ eg‬ﺣﻳﺙ ﺃﻥ ﻁﺎﻗﺔ ﻫﺫﺍ ﺍﻻﻧﺗﻘﺎﻝ ﺗﻘﻊ ﻓﻲ ﻣﻧﻁﻘﺔ ﺍﻟﺿﻭء ﺍﻟﻣﺭﺋﻲ‪.‬‬

‫ﻣﺧﻁﻁ ﺍﻻﻭﺭﺑﻳﺗﺎﻝ ﺍﻟﺟﺯﻳﺋﻲ ‪ MOT‬ﻟﻠﻣﻌﻘﺩﺍﺕ ﺍﻟﺳﺩﺍﺳﻳﺔ ﺍﻟﺗﻧﺎﺳﻕ‪-:‬‬

‫ﻳﺟﺏ ﻣﻌﺭﻓﺔ ﺍﻧﻭﺍﻉ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﻣﻥ ﺣﻳﺙ ﺗﻛﻭﻳﻥ ﺍﻷﻭﺍﺻﺭ‪-:‬‬

‫‪ -‬ﻛﻝ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﻣﺎﻧﺣﺔ ﻵﺻﺭﺓ ﺳﻛﻣﺎ‪.‬‬
‫‪ -‬ﻫﻧﺎﻙ ﻟﻳﻛﺎﻧﺩﺍﺕ ﻣﺎﻧﺣﺔ ﻵﺻﺭﺓ ﺳﻛﻣﺎ ‪ σ‬ﻓﻘﻁ ﻣﺛﻝ ‪.CH3-,H-, NH3‬‬
‫‪ -‬ﻫﻧﺎﻙ ﻟﻳﻛﺎﻧﺩﺍﺕ ﻣﺎﻧﺣﺔ ﻵﺻﺭﺓ ﺳﻛﻣﺎ ‪ σ‬ﻭ ﺁﺻﺭﺓ ﺑﺎﻱ ‪ π‬ﻣﺛﻝ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﺿﻌﻳﻔﺔ )ﺍﻟﺗﻲ ﺗﻣﺗﻠﻙ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ﻓﻲ‬
‫ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ﻏﻳﺭ ﺗﺎﺻﺭﻳﺔ ﻭﻫﻲ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ P‬ﻣﺛﻝ ‪.O2-,CO32-, F- ,CI-,Br-, OH- ,‬‬

‫ﻫﻧﺎﻙ ﻟﻳﻛﺎﻧﺩﺍﺕ ﻣﺎﻧﺣﺔ ﻵﺻﺭﺓ ﺳﻛﻣﺎ ‪ σ‬ﻭ ﻣﺳﺗﻘﺑﻝ ﻟــ ‪ π‬ﻭ ﻣﺛﺎﻟﻬﺎ ‪ ) CO , CN- , phen , bipy‬ﺍﻟﺗﻲ ﺗﻣﺗﻠﻙ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ‬
‫ﺟﺯﻳﺋﻳﺔ ‪ π‬ﺷﺎﻏﺭﺓ( ‪.‬‬

‫ﻣﺧﻁﻁ ﻣﺳﺗﻭﻯ ﻁﺎﻗﺔ ﺍﻟﻣﻌﻘﺩ ﺍﻟﻣﺣﺗﻭﻱ ﻋﻠﻰ ﺭﻭﺍﺑﻁ ﺑﺎﻱ ‪: π‬‬

‫ﺗﺗﻛﻭﻥ ﺍﻟﺭﺍﺑﻁﺔ ﺑﺎﻱ ‪ π‬ﺑﻳﻥ ﺍﻳﻭﻥ ﺍﻟﻔﻠﺯ ﻭ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﻓﻲ ﻣﻌﻘﺩ ﻧﺗﻳﺟﺔ ﺍﻟﺗﺩﺍﺧﻝ ﺑﻳﻥ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻻﻳﻭﻥ ﺍﻟﻔﻠﺯﻱ ‪ t2g‬ﺍﻟﺛﻼﺛﺔ‬

‫) ﺍﻟﻣﺗﺟﻬﺔ ﺑﻔﺻﻭﺻﻬﺎ ﺑﻳﻥ ﺍﻟﻣﺣﺎﻭﺭ( ﻭ ﺑﻳﻥ ﺃﺣﺩ ﺃﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﻘﺎﺩﺭﺓ ﻋﻠﻰ ﺗﻛﻭﻳﻥ ﺭﻭﺍﺑﻁ ﺑﺎﻱ ‪: π‬‬

‫• ﺍﻟﺣﺎﻟﺔ ﺍﻷﻭﻟﻰ ‪:‬ﺗﻛﻭﻳﻥ ﺭﻭﺍﺑﻁ ﻣﻥ ﺍﻟﻧﻭﻉ ﺑﺎﻱ ‪ π‬ﻧﺗﻳﺟﺔ ﺗﺩﺍﺧﻝ ﻣﺩﺍﺭ ﺍﻟﻔﻠﺯﻣﻥ ﺍﻟﻧﻭﻉ ‪ t2g‬ﻣﻊ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ p‬ﻣﻥ‬
‫ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﻠﻳﻛﺎﻧﺩ ﺍﻟﻣﻣﺗﻠﺋﺔ ﺑﺎﻻﻟﻛﺗﺭﻭﻧﺎﺕ‪ ) .‬ﻭ ﻳﻧﺗﺞ ﻋﻧﻬﺎ ﺍﻧﺗﻘﺎﻝ ﺍﻟﺷﺣﻧﺔ ﻣﻥ ﺍﻟﻧﻭﻉ *‪ p π →dπ‬ﺃﻭ ‪(L M‬‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﻭ ﺗﺣﺩﺙ ﻋﻧﺩﻣﺎ ﺗﻛﻭﻥ ﻣﺩﺍﺭﺍﺕ ﺍﻟﻠﻳﻛﺎﻧﺩ ﺫﺍﺕ ﺍﻟﺗﻣﺎﺛﻝ ‪ π‬ﻣﻣﺗﻠﺋﺔ ﺑﺎﻻﻟﻛﺗﺭﻭﻧﺎﺕ ﻭ ﻭﺍﻁﺋﺔ ﻓﻲ ﻁﺎﻗﺗﻬﺎ ﻭ ﻫﺫﻩ ﺗﺗﻣﺛﻝ ﻓﻲ ﻣﺩﺍﺭﺍﺕ ‪p‬‬
‫ﺍﻟﻣﻣﺗﻠﺋﺔ ﻋﻠﻰ ﺃﻳﻭﻧﺎﺕ ¯‪ Cl¯ ، F‬ﻭﻧﺎﺗﺞ ﻫﺫﺍ ﺍﻟﺗﺄﺛﻳﺭ ﻳﺟﻌﻝ ‪ Δ₀‬ﺻﻐﻳﺭﺓ ‪ ،‬ﻟﺫﺍ ﻓﻬﻲ ﺗﻌﺩ ﻟﻳﻛﺎﻧﺩﺍﺕ ﺫﺍﺕ ﻣﺟﺎﻝ ﺿﻌﻳﻑ ﻛﻣﺎ ﻓﻲ‬

‫‪ [MnCI6]4-‬ﻭ ‪.[CrI6]3-‬‬

‫• ﺍﻟﺣﺎﻟﺔ ﺍﻟﺛﺎﻧﻳﺔ ‪:‬ﺗﻛﻭﻳﻥ ﺭﻭﺍﺑﻁ ﻣﻥ ﺍﻟﻧﻭﻉ ﺑﺎﻱ ‪ π‬ﻧﺗﻳﺟﺔ ﺗﺩﺍﺧﻝ ﻣﺩﺍﺭ ﺍﻟﻔﻠﺯﻣﻥ ﺍﻟﻧﻭﻉ ‪ t2g‬ﻣﻊ ﻧﻔﺱ ﺍﻟﻧﻭﻉ ﻣﻥ ﻣﺩﺍﺭﺍﺕ‬
‫ﺍﻟﻠﻳﻛﺎﻧﺩ ﺃﻭ ﻣﻊ ﻣﺩﺭﺍﺭﺍﺕ ﻣﺿﺎﺩﺓ ﻟﻠﺭﺑﻁ **‪ π‬ﻣﻥ ﻣﺩﺍﺭﺍﺕ ﺍﻟﻠﻳﻛﺎﻧﺩ ) ﻭ ﻳﻧﺗﺞ ﻋﻧﻬﺎ ﺍﻧﺗﻘﺎﻝ ﺍﻟﺷﺣﻧﺔ ﻣﻥ ﺍﻟﻧﻭﻉ ‪M →L‬‬
‫()ﺃﻭ ‪( dπ→ pπ‬ﺃﻭ)*‪ . (dπ→ pπ‬ﻭ ﺗﺣﺩﺙ ﻋﻧﺩﻣﺎ ﺗﻛﻭﻥ ﻣﺩﺍﺭﺍﺕ ﺍﻟﻠﻳﻛﺎﻧﺩ ﺫﺍﺕ ﺍﻟﺗﻣﺎﺛﻝ ‪ π‬ﻓﺎﺭﻏﺔ ﻭ ﻋﺎﻟﻳﺔ‬
‫ﺍﻟﻁﺎﻗﺔ ﻭ ﻣﻥ ﺃﻣﺛﻠﺗﻬﺎ ﺗﻠﻙ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﺗﻲ ﺗﺣﺗﻭﻱ ﺫﺭﺍﺕ ﺍﻟﻔﻭﺳﻔﻭﺭ ﻭ ﺍﻟﻛﺑﺭﻳﺕ ﻭ ﺍﻟﺯﺭﻧﻳﺦ ﺍﻟﻭﺍﻫﺑﺔ ﻻﻟﻛﺗﺭﻭﻧﺎﺕ ‪ σ‬ﻭ‬
‫ﺗﻣﺗﻠﻙ ﻣﺩﺍﺭﺍﺕ ﻓﺎﺭﻏﺔ ﻣﻥ ‪ dL‬ﻭ ﺳﺎﻟﺑﻳﺗﻬﺎ ﺍﻟﻛﻬﺭﺑﻳﺔ ﺿﻌﻳﻔﺔ ‪ ،‬ﺃﻭ ﻛﺎﻧﺕ ﻣﺩﺍﺭﺍﺗﻬﺎ **‪ π‬ﺧﺎﻟﻳﺔ ﻣﻥ ﺍﻻﻟﻛﺗﺭﻭﻧﺎﺕ ﻭ ﻳﺷﻣﻝ‬
‫ﻫﺫﺍ ﺍﻟﻧﻭﻉ ﻣﻥ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺗﻠﻙ ﺍﻟﺗﻲ ﺗﺣﺗﻭﻱ ﻋﻠﻰ ﺭﻭﺍﺑﻁ ﻣﺿﺎﻋﻔﺔ ﻣﺛﻝ ¯‪ CO , CN‬ﻭ ﺍﻹﻳﺛﻳﻠﻳﻥ ﻓﻬﺫﻩ ﺗﻣﺗﻠﻙ ﻣﺩﺍﺭﺍﺕ‬
‫ﺟﺯﻳﺋﻳﺔ ﻭ ﻣﺿﺎﺩﺓ ﻟﻠﺭﺑﻁ ﻭ ﻓﺎﺭﻏﺔ ‪ π**L‬ﻭ ﻳﻛﻭﻥ ﻟﻬﺎ ﻁﺎﻗﺔ ﺃﻋﻠﻰ ﻣﻥ ﻁﺎﻗﺎﺕ ﻛﻝ ﻣﻥ ﻣﺩﺍﺭﺍﺕ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﻭ ﺍﻟﻣﺩﺍﺭﺍﺕ‬
‫ﺍﻟﻔﻠﺯﻳﺔ ‪ .‬ﻭ ﺗﺩﻋﻰ ﻣﺛﻝ ﻫﺫﻩ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺑﻠﻳﻛﺎﻧﺩﺍﺕ ﻣﺳﺗﻘـــــــــــــــﺑﻼﺕ ‪ ( π acceptor ligands) π‬؛ ﻭ ﺗﻛﻭﻥ‬
‫ﺍﻟﻣﺣﺻﻠﺔ ﺍﻟﻛﻠﻳﺔ ﻟﻬﺫﺍ ﺍﻟﺗﺄﺛﻳﺭ ﻫﻭ ﺯﻳﺎﺩﺓ ﻗﻳﻣﺔ ‪ Δ₀‬ﻛﻣﺎ ﻓﻲ ﺍﻟﺷﻛﻝ ﺍﻟﺗﺎﻟﻲ ‪ . ([Cr(CN)6]3-‬ﻭ ﻫﺫﻩ ﺗﺳﺑﺏ ﺍﻧﻔﺻﺎﻣﺎ ﻛﺑﻳﺭﺍ‬
‫ﺑﻳﻥ *‪ t2g(π) ,eg‬ﻓﻲ ﺍﻟﻣﺩﺍﺭﺍﺕ ﺍﻟﺟﺯﻳﺋﻳﺔ ﻟﻠﻣﻌﻘﺩ‪ ،‬ﻟﺫﺍ ﻓﻬﻲ ﺗﻌﺩ ﻟﻳﻛﺎﻧﺩﺍﺕ ﺫﺍﺕ ﻣﺟﺎﻝ ﻗﻭﻱ ﻭ ﺗﻭﺿﻊ ﻓﻲ ﺃﻭﻝ ﺍﻟﺳﻠﺳﻠﺔ‬
‫ﺍﻟﻁﻳﻔﻭﻛﻳﻣﻳﺎﺋﻳﺔ ‪ ،‬ﻛﻣﺎ ﻧﻼﺣﻅ ﺃﻥ ﻣﻌﻘﺩﺍﺕ ﺍﻟﻛﺭﺑﻭﻧﻳﻼﺕ ﻋﺩﻳﻣﺔ ﺍﻟﻠﻭﻥ ﺑﺳﺑﺏ ﺍﺑﺗﻌﺎﺩ ﺍﻻﻣﺗﺻﺎﺹ ﺍﻻﻟﻛﺗﺭﻭﻧﻲ ﻋﻥ ﻣﻧﻁﻘﺔ‬

‫ﻁﻳﻑ ﺍﻷﺷﻌﺔ ﺍﻟﻣﺭﺋﻳﺔ ﺇﻟﻰ ﻣﻧﻁﻘﺔ ﻁﻳﻑ ﺍﻷﺷﻌﺔ ﻓﻭﻕ ﺍﻟﺑﻧﻔﺳﺟﻳﺔ ‪.‬‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﻭﻳﺳﻣﻰ ﻫﺫﺍ ﺍﻟﻧﻭﻉ ﻣﻥ ﺍﻟﺗﺂﺻﺭ ﺑﺎﻟﺗﺂﺻﺭ ﺍﻟﺭﺟﻭﻋﻲ ‪ back bonding‬ﺃﻭ ﺑﺎﻟﻭﻫﺏ ﺍﻟﺭﺍﺟﻊ ‪، back donation‬ﻭﻫﺫﺍ ﻳﻘﻠﻝ ﻣﻥ‬
‫ﺗﺭﺍﻛﻡ ﺍﻟﺷﺣﻧﺔ ﺍﻟﺳﺎﻟﺑﺔ ﻋﻠﻰ ﺍﻟﻔﻠﺯ ﻣﻣﺎ ﻳﺟﻌﻝ ‪ Δ‬ﻛﺑﻳﺭﺓ‪ ،‬ﻭﻳﺗﺿﺢ ﺍﻥ ﺍﻟﺗﺎﺻﺭ ﺍﻟﺭﺟﻭﻋﻲ ‪ M CN‬ﻓﻲ ﺍﻟﻣﺭﻛﺏ ‪[Cr(CN)6]3-‬‬

‫ﻳﺯﻳﺩ ﻣﻥ ﺍﻟﺻﻔﺔ ﺍﻟﺗﺳﺎﻫﻣﻳﺔ ﻟﻼﺻﺭﺓ ﺍﻟﺗﻲ ﺗﺭﺑﻁ ﺍﻟﻔﻠﺯ ﺑﺎﻟﻠﻳﻛﺎﻧﺩ ﻭﻛﺫﻟﻙ ﻣﻌﻘﺩﺍﺕ ﺍﻟﻛﺎﺭﺑﻭﻧﻳﻼﺕ ‪.M(CO)n‬‬

‫ﻣﻥ ﺍﻟﺩﺭﺍﺳﺔ ﺍﻟﺳﺎﺑﻘﺔ ﻧﺟﺩ ﺃﻥ ﺗﺩﺍﺧﻝ ﺍﻟﻔﻠﺯ ﻣﻊ ﺍﻟﻠﻳﻛﺎﻧﺩ ﺑﺭﻭﺍﺑﻁ ﻣﻥ ﺍﻟﻧﻭﻉ ‪ π‬ﺗﺳﺗﻁﻳﻊ ﺃﻥ ﺗﻔﺳﺭ ﺍﻟﺳﻠﺳﻠﺔ ﺍﻟﻁﻳﻔﻭﻛﻳﻣﻳﺎﺋﻳﺔ ‪،‬‬
‫ﺣﻳﺙ ﺗﺳﺗﻁﻳﻊ ﺗﻔﺳﻳﺭ ﻗﻭﺓ ‪ CO,CN-‬ﻭ ﺗﻭﺍﺟﺩﻫﺎ ﻓﻲ ﺃﻭﻝ ﺍﻟﺳﻠﺳﻠﺔ ﻭ ﺿﻌﻑ ﺍﻟﻬﺎﻟﻭﺟﻳﻧﺎﺕ ﻭ ﺗﻭﺍﺟﺩﻫﺎ ﻓﻲ ﻧﻬﺎﻳﺔ ﺍﻟﺳﻠﺳﻠﺔ ‪،‬ﺣﻳﺙ‬

‫ﺃﻥ ﺗﺭﺍﺑﻁ ‪ π‬ﻗﺩ ﻳﺯﻳﺩ ﺃﻭ ﻳﻘﻠﻝ ﻣﻥ ﻗﻭﺓ ﺍﻟﻣﺟﺎﻝ ﺍﻟﺑﻠﻭﺭﻱ‪.‬‬
‫ﺑﻳﻧﻣﺎ ﻳﺑﻘﻰ‪ H2O‬ﻭ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﺗﻲ ﻻ ﺗﺭﺗﺑﻁ ﺑﺭﻭﺍﺑﻁ ﻣﻥ ﻧﻭﻉ ﺑﺎﻱ‪ π‬ﻭ ﺗﻛﻭﻥ ﺭﻭﺍﺑﻁ ﻣﻥ ﻧﻭﻉ‪ σ‬ﻓﻘﻁ ﻓﻲ ﻣﻧﺗﺻﻑ ﺍﻟﺳﻠﺳﻠﺔ ‪.‬‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﻣﺛﺎﻝ ‪ :‬ﻛﻳﻑ ﺗﻔﺳﺭ ﺣﻘﻳﻘﺔ ﺃﺯﺩﻳﺎﺩ ‪ Δ₀‬ﺣﺳﺏ ﺗﺳﻠﺳﻝ ﻛﺗﺎﺑﺔ ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻵﺗﻳﺔ‪:‬‬

‫‪[Cr(CI)6]3- < [Cr(NH3)6]3- < [Cr(CN)6]3-‬‬

‫ﺑﺭﻏﻡ ﺍﻟﺷﺣﻧﺔ ﺍﻟﺳﺎﻟﺑﺔ ﻟﻸﻳﻭﻥ ‪ CI-1‬ﻧﻼﺣﻅ ‪ Δ₀‬ﻟﻬﺫﺍ ﺍﻻﻳﻭﻥ ﺍﺻﻐﺭ ﻣﻥ ‪ Δ₀‬ﻟﺟﺯﻳﺋﺔ ‪ NH3‬ﻭﺫﻟﻙ ﺑﺳﺑﺏ ﺗﺄﺛﻳﺭﺍﺕ ﺍﻟﺗﻧﺎﻓﺭ ﺑﻳﻥ‬

‫ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ‪ Pπ‬ﻻﻳﻭﻥ ‪ CI-1‬ﻭﺍﻟﻛﺗﺭﻭﻧﺎﺕ ‪ dπ‬ﻻﻳﻭﻥ ‪ Δ₀ ، Cr3+‬ﻻﻳﻭﻥ ﺍﻟﺳﻳﺎﻧﻳﺩ ‪ CN-1‬ﻛﺑﻳﺭﺓ ﺟﺩﺍً ﻭﺫﻟﻙ ﺑﺳﺑﺏ ﺍﻟﺗﺂﺻﺭ‬

‫‪ Cr‬ﺍﻥ ﺍﻟﻛﺛﺎﻓﺔ ﺍﻻﻟﻛﺗﺭﻭﻧﻳﺔ ﻓﻲ ﺍﻭﺭﺑﻳﺗﺎﻝ ‪ dπ‬ﻻﻳﻭﻥ ‪ Cr+3‬ﺗﻧﺣﺭﻑ ﻧﺣﻭ ﺍﻭﺭﺑﻳﺗﺎﻝ *‪ π‬ﺍﻟﻧﻘﻳﺽ ﺍﻟﺗﺂﺻﺭ ﻓﻲ‬ ‫ﺍﻟﺭﺍﺟﻊ ‪CN‬‬

‫ﺍﻳﻭﻥ ‪ CN-1‬ﻭﻫﺫﺍ ﺍﻟﺗﺄﺛﻳﺭ ﻳﺯﻳﺩ ﻣﻥ ﺍﺳﺗﻘﺭﺍﺭﻳﺔ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ dπ‬ﻓﻳﺟﻌﻝ ‪ Δ₀‬ﻛﺑﻳﺭﺓ‪.‬‬

‫ﻣﺛــــــــﺎﻝ‪ :‬ﻗﺎﺭﻥ ﻧﺗﺎﺋﺞ ﺍﻟﺗﺄﺛﻳﺭ ‪ π‬ﺍﻟﻣﺗﺑﺎﺩﻝ ﻓﻲ ﻣﻌﻘﺩﻱ ‪ [Fe(CN)6]4-‬ﻭ ‪.[FeF6]3-‬‬
‫ﺍﻥ ﺍﻳﻭﻥ ﺍﻟﺳﻳﺎﺗﻳﺩ ﻓﻲ ﺍﻟﻣﺭﻛﺏ ﺍﻻﻭﻝ ﻳﻣﺗﻠﻙ ﺍﻭﺭﺑﻳﺗﺎﻝ ‪ π‬ﺷﺎﻏﺭﺍً ﻣﻣﺎﺛﻝ ﻻﻭﺭﺑﻳﺗﺎﻝ ﺍﻟﺣﺩﻳﺩ ﺍﻟﻣﻣﺗﻠﺊ ) ﺍﻭﺭﺑﻳﺗﺎﻝ ‪ ( t2g‬ﻟﻛﻧﻪ ﺫﻭ‬
‫ﻁﺎﻗﺔ ﺍﻋﻠﻰ ﻳﻣﺗﻠﻙ ﺍﻳﻭﻥ ﺍﻟﻔﻠﻭﺭﻳﺩ ﻓﻲ ﺍﻟﻣﺭﻛﺏ ﺍﻟﺛﺎﻧﻲ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ﻏﻳﺭ ﺗﺎﺻﺭﻳﺔ ﻣﻣﺗﻠﺋﺔ ﺫﺍﺕ ﺗﻧﺎﻅﺭ ﻣﺷﺎﺑﻪ ﻟﻛﻧﻬﺎ ﺫﺍﺕ ﻁﺎﻗﺔ ﺍﻭﻁﺄ‬

‫ﻣﻥ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﺣﺩﻳﺩ ‪.‬ﺃﺭﺳﻡ ﻣﺧﻁﻁﻳﻥ ﻟﻣﺳﺗﻭﻳﺎﺕ ﺍﻟﻁﺎﻗﺔ ﺑﺑﻳﺎﻥ ﻛﻳﻔﻳﺔ ﺣﺻﻭﻝ ﻫﺫﻩ ﺍﻟﺗﺄﺛﻳﺭﺍﺕ‪.‬‬
‫ﻣﺛـــــــــــــﺎﻝ‪ :‬ﻗﺎﺭﻥ ‪ Δ₀‬ﻟﻣﻌﻘﺩﻱ ﻻﻳﻭﻥ ‪ d6‬ﻳﺣﺗﻭﻱ ﺍﻻﻭﻝ ﻋﻠﻰ ﺍﻳﻭﻥ ‪ OH-‬ﻭﻳﺣﺗﻭﻱ ﺍﻟﺛﺎﻧﻲ ﻋﻠﻰ ﺟﺯﻳﺋﺔ ‪.PH3‬؟‬
‫ﺗﺣﺗﻭﻱ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ t2g‬ﻓﻲ ﻫﺫﺍ ﺍﻻﻳﻭﻥ ﻋﻠﻰ ﺳﺗﺔ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ‪ ،‬ﺍﻟﻣﻌﻘﺩ ﺍﻟﺫﻱ ﻳﺣﺗﻭﻱ ﻋﻠﻰ ﺍﻳﻭﻥ ‪ OH-‬ﻳﺣﺗﻭﻱ ﻋﻠﻰ‬
‫ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ π‬ﻣﻣﺗﻠﺋﺔ ﻭﻳﻌﻁﻲ ﻣﻊ ﺍﻳﻭﻥ ﺍﻟﻔﻠﺯ ﺍﻟﺗﺂﺻﺭ ‪ M OH- π‬ﻭﻫﺫﺍ ﺍﻟﺗﺄﺛﻳﺭ ﻳﻌﻣﻝ ﻋﻠﻰ ﺯﻳﺎﺩﺓ ﺍﻟﻛﺛﺎﻓﺔ ﺍﻻﻟﻛﺗﺭﻭﻧﻳﺔ ﻓﻲ‬

‫ﺍﻳﻭﻥ ﺍﻟﻔﻠﺯ ﻭ ﻳﻘﻠﻝ ﻣﻥ ﺍﺳﺗﻘﺭﺍﺭﻳﺔ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ t2g‬ﻓﺗﺻﺑﺢ ‪ Δ₀‬ﺻﻐﻳﺭﺓ‪.‬‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫‪ M‬ﺍﻟﺭﺍﺟﻊ ﻭﻫﺫﺍ ﺍﻟﺗﺂﺻﺭ ﻳﻘﻠﻝ ﻣﻥ ﺍﻟﺷﺣﻧﺔ‬ ‫ﺍﻟﻣﻌﻘﺩ ﺍﻟﺫﻱ ﻳﺣﺗﻭﻱ ﻋﻠﻰ ﺟﺯﻳﺋﺔ ‪ PH3‬ﻳﺣﺻﻝ ﻓﻲ ﻫﺫﻩ ﺍﻟﺣﺎﻟﺔ ﺍﻟﺗﺂﺻﺭ ‪L‬‬

‫ﺍﻟﺳﺎﻟﺑﺔ ﻋﻠﻰ ﺍﻟﻔﻠﺯ ﻭﻳﺿﻌﻬﺎ ﻓﻲ ﺍﺣﺩ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ PH3‬ﻏﻳﺭ ﺍﻟﺗﺂﺻﺭﻳﺔ ﺍﻟﺷﺎﻏﺭﺓ ﻭﻫﺫﺍ ﺍﻟﺗﺄﺛﻳﺭ ﻳﺯﻳﺩ ﻣﻥ ﺍﺳﺗﻘﺭﺍﺭﻳﺔ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ‬

‫‪ t2g‬ﻓﺗﺻﺑﺢ ‪ Δ₀‬ﻛﺑﻳﺭﺓ‪.‬‬

‫ﺱ ‪ :‬ﻛﻳﻑ ﺗﻔﺳﺭ ﻧﻅﺭﻳﺔ ﺍﻻﻭﺭﺑﻳﺗﺎﻝ ﺍﻟﺟﺯﻳﺋﻲ ﻣﻭﻗﻌﻲ ‪ CI-‬ﻭ ‪ NO2-‬ﻓﻲ ﺍﻟﺳﻠﺳﻠﺔ ﺍﻟﻁﻳﻔﻭ ﻛﻳﻣﻳﺎﺋﻳﺔ ؟‬
‫ﺱ ‪:‬ﺃﺭﺳﻡ ﻣﺧﻁﻁﺎً ﻟﻣﺳﺗﻭﻳﺎﺕ ﻁﺎﻗﺔﺍﻻﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﺟﺯﻳﺋﻳﺔ ﻟﻠﻣﻌﻘﺩ ‪ [Ni(NH3)6]2+‬ﻣﺑﻳﻧﺎً ﺃﺷﻐﺎﻝ ﺍﻻﻭﺭﺑﻳﺗﺎﻻﺕ ؟‬
‫ﺱ‪ :‬ﺃﺫﺍ ﻋﻠﻣﺕ ﺃﻥ ‪ Δ₀‬ﻟﻣﻌﻘﺩ ‪ [Fe(H2O)6]2+‬ﺗﺳﺎﻭﻱ ‪ 10400 Cm-1‬ﻣﺎﻫﻲ ﻁﺎﻗﺔ ﺍﺳﺗﻘﺭﺍﺭ ﺍﻟﻣﺟﺎﻝ ﺍﻟﺑﻠﻭﺭﻱ ﻟﻬﺫﺍ ﺍﻻﻳﻭﻥ؟‬

‫ﺱ‪:‬ﺍﻟﻣﺭﻛﺏ ‪ [Fe(H2O)6]3+‬ﺫﻭ ﺑﺭﻡ ﻋﺎﻝ ‪ ،‬ﻟﻛﻥ ﺍﻟﻣﺭﻛﺏ ‪ [Fe(CN)6]3-‬ﺫﻭ ﺑﺭﻡ ﻭﺍﻁﺊ‪ .‬ﻓﺳﺭ ﺫﻟﻙ؟‬
‫ﺱ‪ :‬ﻳﺗﺧﺫ ﺍﻳﻭﻥ ‪ Fe3+‬ﻓﻲ ﻣﻌﻘﺩﺍﺗﻪ ﺍﻟﺷﻛﻝ ﺍﻟﺛﻣﺎﻧﻲ ﺍﻟﺳﻁﻭﺡ‪ .‬ﺃﻳﻬﻣﺎ ﺃﻛﺛﺭ ﺍﺳﺗﻘﺭﺍﺭﺍً ﻟﻬﺫﺍ ﺍﻻﻳﻭﻥ ﻣﺭﻛﺑﺎﺕ ﺍﻟﺑﺭﻡ ﺍﻟﻌﺎﻟﻲ ﺃﻡ‬

‫ﻣﺭﻛﺑﺎﺕ ﺍﻟﺑﺭﻡ ﺍﻟﻭﺍﻁﺊ؟‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﻣﺧﻁﻁ ﻣﺳﺗﻭﻳﺎﺕ ﻁﺎﻗﺔ ﺍﻻﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﺟﺯﻳﺋﻳﺔ ﻓﻲ ‪[Co(NH3)6]3+‬‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﻣﺧﻁﻁ ﻣﺳﺗﻭﻳﺎﺕ ﻁﺎﻗﺔ ﺍﻻﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﺟﺯﻳﺋﻳﺔ ﻓﻲ ‪[CoF6]3+‬‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﺗﻁﺑﻳﻕ ﺍﻟﻧﻅﺭﻳﺔ ﻋﻠﻰ ﻣﻌﻘﺩ ﺭﺑﺎﻋﻲ ﺍﻟﺳﻁﻭﺡ )‪: (tetrahedral‬‬

‫ﺇﺫﺍ ﺍﻋﺗﺑﺭﻧﺎ ﻣﻌﻘﺩ ﺭﺑﺎﻋﻲ ﺍﻟﺳﻁﻭﺡ ‪ ML4‬ﻭ ﺍﻓﺗﺭﺿﻧﺎ ﺑﺄﻥ ﺗﺭﺍﺑﻁ ‪ σ‬ﻫﻭ ﺍﻟﻣﻬﻡ ﻓﻘﻁ ‪.‬‬
‫ﻧﺟﺩ ﺃﻥ ﺍﻷﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﺫﺭﻳﺔ ﺍﻟﻣﻧﺎﺳﺑﺔ ﻟﺗﻛﻭﻳﻥ ﺭﻭﺍﺑﻁ ﻣﻥ ﻧﻭﻉ ‪ σ‬ﻛﺎﻟﺗﺎﻟﻲ ‪:‬‬

‫)‪4s(a1g) , 3dx-y , 3dx-z , 3dy-z (t2g‬‬
‫ﺃﻣﺎ ﺍﻷﻭﺭﺑﻳﺗﺎﻻﺕ )‪ 3dz2 , 3dx2-y2 (eg‬ﻓﻬﻣﺎ ﻳﺳﺗﻌﻣﻼﻥ ﻟﻠﺗﺂﺻﺭ‪ π‬ﻓﻘﻁ ‪.‬‬

‫ﻭﻟﺭﺳﻡ ﻣﺧﻁﻁ ﻻﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﺟﺯﻳﺋﻳﺔ ﺍﻟﻣﺗﺿﻣﻥ ﺍﻟﺗﺂﺻﺭ ‪ σ‬ﻓﻘﻁ ﻧﺳﺗﻌﻣﻝ ﺍﻻﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﻔﻠﺯﻳﺔ ﺃﻋﻼﻩ ﻣﻊ ﺍﻻﻭﺭﺑﻳﺗﺎﻻﺕ ‪σ‬‬
‫ﺍﻟﺧﺎﺻﺔ ﺑﺎﻟﻠﻳﻛﺎﻧﺩ ﻛﻣﺎ ﻣﺑﻳﻥ ﺃﺩﻧﺎﻩ‪:‬‬

‫ﻣﺧﻁﻁ ﻣﺳﺗﻭﻯ ﻁﺎﻗﺔ ﺍﻟﻣﻌﻘﺩ ‪ ML4‬ﺍﻟﺷﻛﻝ ﺍﻟﺭﺑﺎﻋﻲ ﺍﻷﻭﺟﻪ‬
‫ﺍﻟﻣﻼﺣﻅﺎﺕ ﺣﻭﻝ ﺍﻟﺷﻛﻝ ‪:‬‬

‫‪ -‬ﺍﻻﻭﺭﺑﻳﺗﺎﻻﺕ ﺍﻟﺟﺯﻳﺋﻳﺔ ﺫﺍﺕ ﺍﻟﻁﺎﻗﺔ ﺍﻻﻭﻁﺄ ﻫﻲ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ t2g , a1g‬ﺍﻟﺗﻲ ﺗﺗﺳﻊ ﻻﺭﺑﻌﺔ ﻣﺯﺩﻭﺟﺎﺕ ﺍﻟﻛﺗﺭﻭﻧﻳﺔ‬
‫ﺍﻟﺗﻲ ﻳﻬﺑﻬﺎ ﺍﻟﻠﻳﻛﺎﻧﺩ ‪.‬‬

‫‪ -‬ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ eg‬ﻫﻲ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ﻏﻳﺭ ﺗﺂﺻﺭﻳﺔ ‪.‬‬
‫‪ -‬ﺗﻭﺿﻊ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ‪ d‬ﻟﻠﻔﻠﺯ ﻓﻲ ﺍﻭﺭﺑﻳﺗﺎﻻﺕ ‪ eg‬ﻭ *‪ t2g‬ﻭﻓﺭﻕ ﺍﻟﻁﺎﻗﺔ ﺑﻳﻥ ﻫﺫﻩ ﺍﻻﻭﺭﺑﻳﺗﺎﻻﺕ ﺻﻐﻳﺭ ﻭﻟﻬﺫﺍ ﻳﻼﺣﻅ ﺗﺭﻛﻳﺏ‬

‫ﺍﻟﺑﺭﻡ ﺍﻟﻌﺎﻟﻲ ﻷﻏﻠﺏ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﺭﺑﺎﻋﻳﺔ ﺍﻟﺳﻁﻭﺡ ‪.‬‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫)‪Effect Atomic Number Rule (EAN‬‬ ‫‪ -‬ﻗﺎﻋﺩﺓ ﺍﻟﻌﺩﺩ ﺍﻟﺫﺭﻱ ﺍﻟﻔﻌﺎﻝ‪:‬‬

‫ﻓﻲ ﻧﻅﺭﻳﺔ ﻓﺭﻧﺭ ﺍﻟﺑﺳﻳﻁﺔ ﻟﻠﻣﻌﻘﺩﺍﺕ ‪ ،‬ﺗﺗﻛﻭﻥ ﺍﻟﺭﻭﺍﺑﻁ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ﺑﻳﻥ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﻭ ﺃﻳﻭﻥ ﺍﻟﻔﻠﺯ ﺍﻟﻣﺭﻛﺯﻱ ﻓﻲ ﻛﺭﺓ ﺍﻟﺗﻧﺎﺳﻕ‪.‬‬
‫ﺣﻳﺙ ﻳﻌﻁﻲ ﺍﻟﻠﻳﻛﺎﻧﺩ ﺯﻭﺝ ﺍﻟﻛﺗﺭﻭﻧﺎﺕ ﺇﻟﻰ ﺍﻟﺫﺭﺓ ﺍﻟﻣﺭﻛﺯﻳﺔ ‪ .‬ﻭ ﺗﺗﻛﻭﻥ ﺍﻟﻣﺭﻛﺑﺎﺕ ﺑﺻﻭﺭﺓ ﻭﺍﺳﻌﺔ ﻭ ﻛﺑﻳﺭﺓ ﻣﻊ ﺍﻟﻌﻧﺎﺻﺭ ﺍﻻﻧﺗﻘﺎﻟﻳﺔ‬
‫ﻧﻅﺭﺍ ﻻﺣﺗﻭﺍﺋﻬﺎ ﻋﻠﻰ ﻣﺩﺍﺭﺍﺕ ‪ d‬ﻓﺎﺭﻏﺔ ﻭ ﺍﻟﺗﻲ ﻳﻣﻛﻥ ﺃﻥ ﺗﺣﻭﻱ ﺃﺯﻭﺍﺝ ﺍﻹﻟﻛﺗﺭﻭﻧﺎﺕ ﺍﻟﻣﻌﻁﺎﺓ ‪ .‬ﻭ ﻳﻌﺗﻣﺩ ﻋﺩﺩ ﺍﻟﺭﻭﺍﺑﻁ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ‬

‫ﻭ ﺍﻟﺗﻲ ﻳﻣﻛﻥ ﺃﻥ ﺗﺗﻛﻭﻥ ﺑﺩﺭﺟﺔ ﻛﺑﻳﺭﺓ ﻋﻠﻰ ﻋﺩﺩ ﺍﻟﻣﺩﺍﺭﺍﺕ ﺍﻟﻔﺎﺭﻏﺔ ﺫﺍﺕ ﺍﻟﻁﺎﻗﺔ ﺍﻟﻣﻧﺎﺳﺑﺔ ‪.‬‬

‫ﻭ ﺗﻘﺩﻣﺕ ﺃﻭﻝ ﻣﺣﺎﻭﻟﺔ ﻟﺗﻔﺳﻳﺭ ﺍﻟﺗﺭﺍﺑﻁ ﻣﻥ ﻗﺑﻝ ﺳﻳﺟﻭﻳﻙ ‪ sidgwick‬ﻟﺗﻔﺳﻳﺭ ﻛﻳﻔﻳﺔ ﺣﺩﻭﺙ ﻫﺫﻩ ﺍﻟﺭﻭﺍﺑﻁ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ‪.‬‬

‫ﺗﻌﺗﺑﺭ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﻣﺗﺻﻠﺔ ﺑﺎﻟﺫﺭﺓ ﺍﻟﻣﺭﻛﺯﻳﺔ ﻗﻭﺍﻋﺩ ﺣﺳﺏ ﻣﻔﻬﻭﻡ ﻟﻭﻳﺱ )ﺣﻳﺙ ﺗﻣﻧﺢ ﻛﻝ ﻣﻧﻬﺎ ﺯﻭﺟﺎ ﻣﻥ ﺍﻻﻟﻛﺗﺭﻭﻧﺎﺕ( ﺇﻟﻰ‬
‫ﺍﻟﺫﺭﺓ ﺃﻭ ﺍﻷﻳﻭﻥ ﺍﻟﻣﺭﻛﺯﻱ ﻓﻲ ﺍﻟﻣﺭﻛﺏ ﺍﻟﻣﻌﻘﺩ‪ .‬ﻭﺗﻌﺗﺑﺭ ﺍﻟﺫﺭﺓ ﺍﻟﻣﺭﻛﺯﻳﺔ ﺣﺎﻣﺽ ) ﺣﻳﺙ ﺗﺳﺗﻘﺑﻝ ﺯﻭﺝ ﺍﻻﻟﻛﺗﺭﻭﻧﺎﺕ( ﺣﺳﺏ‬

‫ﻣﻔﻬﻭﻡ ﻟﻭﻳﺱ‪.‬‬

‫ﻓﺭﺽ ﺳﻳﺟﻭﻳﻙ ﺃﻥ ﺍﺳﺗﻘﺭﺍﺭ ﺍﻷﻳﻭﻧﺎﺕ ﺍﻟﻣﻌﻘﺩﺓ ﻳﺗﻭﻗﻑ ﻋﻠﻰ ﺗﻣﺎﺛﻝ ﺗﺭﺗﻳﺑﻬﺎ ﺍﻻﻟﻛﺗﺭﻭﻧﻲ ﻣﻊ ﺍﻟﺗﺭﺗﻳﺏ ﺍﻻﻟﻛﺗﺭﻭﻧﻲ ﻟﻠﻐﺎﺯﺍﺕ‬
‫ﺍﻟﺧﺎﻣﻠﺔ‪.‬ﻓﻳﺻﺑﺢ ﺍﻷﻳﻭﻥ ﺍﻟﻣﻌﻘﺩ ﻣﺳﺗﻘﺭﺍ ﺇﺫﺍ ﻛﺎﻥ ﻣﺟﻣﻭﻉ ﺍﻻﻟﻛﺗﺭﻭﻧﺎﺕ ﺍﻟﻣﻭﺟﻭﺩﺓ ﻋﻠﻰ ﺍﻟﻔﻠﺯ ﺃﻭ ﺍﻷﻳﻭﻥ ﺍﻟﻣﺭﻛﺯﻱ ﻭ ﺍﻹﻟﻛﺗﺭﻭﻧﺎﺕ‬

‫ﺍﻟﻣﻣﻧﻭﺣﺔ ﻣﻥ ﻗﺑﻝ ﺍﻟﻠﻳﻛﺎﻧﺩ ﻳﺳﺎﻭﻱ ﺍﻟﻌﺩﺩ ﺍﻟﺫﺭﻱ ﻟﻠﻐﺎﺯ ﺍﻟﺧﺎﻣﻝ ‪.‬‬

‫ﺗﻧﻁﺑﻕ ﻫﺫﻩ ﺍﻟﻘﺎﻋﺩﺓ ﻋﻠﻰ ﻋﺩﺩ ﻷﺑﺄﺱ ﺑﻪ ﻣﻥ ﺍﻟﻣﻌﻘﺩﺍﺕ ﻭ ﺧﺎﺻﺔ ﺍﻟﻛﺭﺑﻭﻧﻳﻼﺕ ﻭ ﺍﻟﻧﺗﺭﻭﺯﻳﻼﺕ‪ ،‬ﻭ ﻧﺟﺣﺕ ﻣﻊ ﺩﺍﻳﻣﺭﺍﺕ ﺍﻟﻌﻧﺎﺻﺭ‬
‫ﺍﻟﻔﻠﺯﻳﺔ ﻭ ﺑﺻﻔﺔ ﻋﺎﻣﺔ ﻧﺟﺣﺕ ﻣﻊ ﺍﻟﻔﻠﺯﺍﺕ ﺍﻟﺗﻲ ﻟﻬﺎ ﺍﻟﺗﺭﺗﻳﺏ ﺍﻻﻟﻛﺗﺭﻭﻧﻲ ‪nd10(n+1)s0‬‬

‫‪He:2 , Ne:10 , Ar:18 , Kr: 36 , Xe: 54 , Rn: 86‬‬

‫ﺃﻣﺛﻠﺔ ﺗﺑﻳﻥ ﺑﻌﺽ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﻣﺳﺗﻘﺭﺓ ﻭ ﺍﻟﺗﻲ ﺗﻧﻁﺑﻕ ﻋﻠﻳﻬﺎ ﺍﻟﻘﺎﻋﺩﺓ‪:‬‬

‫‪[ptCl6]2-‬‬ ‫‪Ag =47e‬‬ ‫‾‪[Co(NO2)6]3‬‬

‫‪Pt =78e‬‬ ‫‪Ag+ =46e‬‬ ‫‪Co3+ = 24 e‬‬

‫‪Pt4+=76e‬‬ ‫‪4NH3=12e‬‬ ‫‪6NO2‾ = 12 e‬‬

‫‪6Cl-=6x2=12e‬‬ ‫)‪[Ag(NH3)4]+ =54 e (Xe) [Co(NO2)6]3‾=36e (Kr‬‬

‫)‪[PtCl6]-2=86e (Rn‬‬

‫ﻛﻣﺎ ﻻﺣﻅﻧﺎ ﻓﺄﻥ ﺍﻳﻭﻥ ﺍﻟﻔﺿﺔ ﻳﻛﻭﻥ ﻣﻊ ﺍﻻﻣﻭﻧﻳﺎ ﻣﻌﻘﺩ ﺍﻟﻔﺿﺔ ﺍﻟﺛﺎﺑﺕ ‪ ) [Ag(NH3)4]+‬ﺍﻟﺫﻱ ﻳﺗﺑﻊ ﺍﻟﻘﺎﻋﺩﺓ )‪ (EAN‬ﺍﻻ ﺍﻧﻪ‬

‫ﺍﻗﻝ ﺛﺑﺎﺗﺎً ﻣﻥ ‪ [Ag(NH3)2]+‬ﻭﻋﻧﺩ ﺣﺳﺎﺏ ﺍﻟﻌﺩﺩ ﺍﻟﺫﺭﻱ ﻟﻸﺧﻳﺭ ﻧﺟﺩ ﺑﺄﻧﻪ ﻻ ﻳﺗﻔﻕ ﻣﻊ ﺍﻟﻘﺎﻋﺩﺓ ﺣﻳﺙ ﺇﻥ ﺍﻟﻌﺩﺩ ﺍﻟﻛﻠﻲ‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﻟﻼﻟﻛﺗﺭﻭﻧﺎﺕ ﻫﻧﺎ ﻫﻭ ‪ 50‬ﻓﻘﻁ ‪ .‬ﻭﻫﻧﺎﻙ ﻣﻌﻘﺩﺍﺕ ﺃﺧﺭﻯ ﻻ ﺗﺗﺑﻊ ﺍﻟﻘﺎﻋﺩﺓ ﺃﻳﺿﺎً ﻭﻫﻲ ‪[Cr(NH3)6]+3 ,[Ni(NH3)6]+2‬‬
‫‪ ,[CoCI4]2-‬ﻭﻧﺗﻳﺟﺔ ﻟﻬﺫﻩ ﺍﻻﺳﺗﺛﻧﺎءﺍﺕ ﻧﺟﺩ ﺃﻥ ﺃﻫﻣﻳﺔ ﻫﺫﻩ ﺍﻟﻘﺎﻋﺩﺓ ﻗﻠﻳﻠﺔ ﺇﻻ ﺃﻧﻬﺎ ﻣﻔﻳﺩﺓ ﻓﻲ ﻣﺟﺎﻝ ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻟﻌﺿﻭﻳﺔ‬

‫ﺍﻟﻔﻠﺯﻳﺔ ﺍﻟﻛﺭﺑﻭﻧﻳﻼﺕ ﻛﻣﺎ ﻓﻲ ﺍﻟﻛﺭﺑﻭﻧﻳﻼﺕ ﺍﻟﺗﺎﻟﻳﺔ ‪-:‬‬

‫‪Ni(CO)4‬‬ ‫‪Fe(CO)5‬‬ ‫‪Cr(CO)6‬‬
‫‪Ni =28‬‬ ‫‪Fe =26e‬‬ ‫‪Cr =24e‬‬
‫‪4CO =8e‬‬ ‫‪5CO =10e‬‬ ‫‪6CO =12e‬‬
‫‪[Ni(CO)4] =36e‬‬ ‫‪[Fe(CO)5] =36e‬‬ ‫‪[Cr(CO)6] =36e‬‬

‫]‪[Fe2(CO)9‬‬ ‫]‪[Co2(CO)8‬‬ ‫]‪[Mn2(CO)10‬‬
‫‪Fe =26e‬‬ ‫‪Co =27e‬‬ ‫‪Mn=25e‬‬
‫‪3CO=6e‬‬ ‫‪3CO =6e‬‬ ‫‪5CO=10e‬‬

‫‪3CO(bridge)=3e‬‬ ‫‪2CO(bridge) =2e‬‬ ‫‪Mn-Mn =1e‬‬
‫‪Fe-Fe =1e‬‬ ‫‪Co-Co =1e‬‬ ‫‪EAN =36e‬‬
‫‪EAN =36e‬‬ ‫‪EAN =36 e‬‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫ﺍﻟﺗﺷﺎﺑﻪ ﺍﻟﺟﺯﻳﺋﻲ ﻓﻲ ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ‪:‬‬

‫‪Isomerism in metal complexes‬‬

‫ﻋﻧﺩﻣﺎ ﺗﺣﺗﻭﻱ ﺍﻟﻣﺭﻛﺑﺎﺕ ﻋﻠﻰ ﺍﻟﺻﻳﻐﺔ ﺍﻟﻛﻳﻣﻳﺎﺋﻳﺔ ﺍﻟﺟﺯﻳﺋﻳﺔ ﻧﻔﺳﻬﺎ ﻭ ﺗﺧﺗﻠﻑ ﻓﻲ ﺍﻟﺗﻭﺯﻳﻊ ﺍﻻﻟﻛﺗﺭﻭﻧﻲ ﺃﻭ ﺍﻟﺗﻭﺟﻪ ﺍﻟﻔﺭﺍﻏﻲ‬
‫ﻓﻲ ﺍﻟﻔﺿﺎء‪ ،‬ﺗﻌﺭﻑ ﺑﺎﻟﺗﺷﺎﺑﻪ ﺍﻟﺟﺯﻳﺋﻲ )‪.(Isomerism‬ﻭﺗﻌﻁﻲ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﻔﻠﺯﻳﺔ ﺃﻧﻭﺍﻋﺎ ﻣﺧﺗﻠﻔﺔ ﻣﻥ ﺍﻻﻳﺯﻭﻣﺭﻳﺔ ‪ ،‬ﻭﻳﻣﻛﻥ ﺗﻘﺳﻳﻡ‬

‫ﺍﻹﻋﺩﺍﺩ ﺍﻟﻛﺑﻳﺭﺓ ﻟﻼﻳﺯﻭﻣﺭﺍﺕ ﺇﻟﻰ ﺻﻧﻔﻳﻥ ﻭﺍﺳﻌﻳﻥ‪:‬‬

‫‪ -1‬ﺍﻟﺗﺷﺎﺑﻪ ﺍﻟﻬﻧﺩﺳﻲ ﺃﻭ ﺍﻟﺗﺷﺎﺑﻪ ﺍﻟﻔﺭﺍﻏﻲ‪Geometrical Isomerisation or Stereoisomerism :‬‬

‫ﺗﺳﺗﻁﻳﻊ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﻓﻲ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺍﻟﻔﻠﺯﻳﺔ ﺃﻥ ﺗﺣﺗﻝ ﻣﻭﺍﻗﻊ ﻣﺧﺗﻠﻔﺔ ﺣﻭﻝ ﺍﻟﺫﺭﺓ ﺍﻟﻣﺭﻛﺯﻳﺔ ﻭ ﻳﻣﻛﻥ ﺇﻥ ﺗﻘﻊ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺍﻟﻣﻌﻳﻧﺔ‬
‫ﺑﺷﻛﻝ ﻣﺗﺟﺎﻭﺭ )‪ (cis-‬ﺃﻭ ﻳﻘﺎﺑﻝ ﺃﺣﺩﻫﺎ ﺍﻷﺧﺭ )‪، (trans-‬ﻭ ﻻ ﺗﺳﺗﻁﻳﻊ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺫﺍﺕ ﺍﻹﻋﺩﺍﺩ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ‪ 2,3‬ﻭﻛﺫﻟﻙ ﺍﻟﻣﻌﻘﺩﺍﺕ‬

‫ﺭﺑﺎﻋﻳﺔ ﺍﻟﺳﻁﻭﺡ ﺃﻥ ﺗﻌﻁﻲ ﻫﺫﺍ ﺍﻟﻧﻭﻉ ﻣﻥ ﺍﻻﻳﺯﻭﻣﺭﻳﺔ ﺇﺫ ﺗﻛﻭﻥ ﺟﻣﻳﻊ ﺍﻟﻣﻭﺍﻗﻊ ﺍﻟﺗﻧﺎﺳﻘﻳﺔ ﻓﻲ ﻫﺫﻩ ﺍﻷﻧﻅﻣﺔ ﻣﺗﺟﺎﻭﺭﺓ ‪ .‬ﺍﻻﻳﺯﻭﻣﺭﻳﺔ‬
‫)‪ cis-trans‬ﻳﻛﻭﻥ ﺷﺎﺋﻌﺎً ﻓﻲ ﻣﻌﻘﺩﺍﺕ ﺍﻟﻣﺭﺑﻊ ﺍﻟﻣﺳﺗﻭﻱ ﻭ ﺛﻣﺎﻧﻲ ﺍﻟﺳﻁﻭﺡ ‪،‬ﻭ ﺗﻌﺗﺑﺭ ﻣﻌﻘﺩﺍﺕ ﺍﻟﺑﻼﺗﻳﻥ )‪ (II‬ﺃﺣﺳﻥ ﺍﻷﻣﺛﻠﺔ‬

‫ﺍﻟﻣﻌﺭﻭﻓﺔ ﻟﻠﻣﻌﻘﺩﺍﺕ ﺍﻟﺗﻲ ﻟﻬﺎ ﺗﺭﻛﻳﺏ ﺍﻟﻣﺭﺑﻊ ﺍﻟﻣﺳﺗﻭﻱ ‪ ، square planar‬ﻓﻳﻣﻛﻥ ﺗﺣﺿﻳﺭ ﺷﺑﻳﻬﻳﻥ ﻫﻧﺩﺳﻳﻳﻥ‬
‫ﻟﻠﻣﺗﺭﺍﻛﺏ]‪. [Pt(NH3)Cl2‬‬

‫‪Cl NH3‬‬ ‫‪Cl NH3‬‬
‫‪Pt‬‬ ‫‪Pt‬‬

‫‪Cl NH3‬‬ ‫‪H3N‬‬ ‫‪Cl‬‬

‫‪Cis Trans‬‬

‫ﻳﺣﺿﺭ ﺍﻟﺷﺑﻳﻪ ﺍﻟﻣﺟﺎﻭﺭ‪ cis‬ﺑﺗﻔﺎﻋﻝ ‪ K2PtCl4‬ﻣﻊ ﻣﺣﻠﻭﻝ ﺍﻷﻣﻭﻧﻳﺎ ﺍﻟﻣﺎﺋﻲ‪ k2[PtCl4]+ NH4OH :‬ﻭﻳﻛﻭﻥ ﻟﻠﻣﻌﻘﺩ ﻋﺯﻡ‬
‫ﻗﻁﺑﻲ‪.‬‬

‫ﻭ ﻳﺣﺿﺭ ﺍﻟﺷﺑﻳﻪ ﺍﻟﻣﺗﻌﺎﻛﺱ ﺃﻭ ﺍﻟﻣﺿﺎﺩ ‪ trans‬ﺑﺈﺿﺎﻓﺔ ‪ HCI‬ﺇﻟﻰ ﺃﻳﻭﻥ ‪ [Pt(NH3)4]2+‬ﻭ ﻻ ﻳﻛﻭﻥ ﻟﻠﻣﻌﻘﺩ ﻋﺯﻡ ﻗﻁﺑﻲ ﻧﻅﺭﺍ‬
‫ﻟﻭﺟﻭﺩ ﻣﺭﻛﺯ ﺗﻣﺎﺛﻝ‪.‬‬

‫ﻭ ﺑﺫﻟﻙ ﻧﺳﺗﻁﻳﻊ ﺍﻟﺗﻣﻳﻳﺯ ﺑﻳﻥ ﺍﻟﻧﻭﻋﻳﻥ ﺳﻳﺯ ﻭ ﺗﺭﺍﻧﺱ ﺑﻘﻳﺎﺱ ﺍﻟﻌﺯﻡ ﺍﻟﻘﻁﺑﻲ ﻟﻛﻝ ﻣﻧﻬﻣﺎ‪ ، ،‬ﻭﺃﻳﺿﺎ ﻣﻥ ﺧﻼﻝ ﺍﺳﺗﺧﺩﺍﻡ ﺣﻳﻭﺩ‬
‫ﺍﻷﺷﻌﺔ ﺍﻟﺳﻳﻧﻳﺔ‪.‬‬

‫ﻭﻟﻘﺩ ﻭﺟﺩﺕ ﺍﻻﻳﺯﻭﻣﺭﻳﺔ ﺍﻟﻬﻧﺩﺳﻳﺔ ﺃﻳﺿﺎ ﻓﻲ ﺍﻷﻧﻅﻣﺔ ﺍﻟﻣﺭﺑﻌﺔ ﺍﻟﻣﺳﺗﻭﻳﺔ ﺍﻟﺗﻲ ﺗﺣﺗﻭﻱ ﻋﻠﻰ ﻟﻳﻛﺎﻧﺩﺍﺕ ﺛﻧﺎﺋﻳﺔ ﺍﻟﺳﻥ ﻏﻳﺭ ﺍﻟﻣﺗﻣﺎﺛﻠﺔ‬
‫]‪ (unsymmetric bidentate ligands)[M(AB)2‬ﻭﻣﻥ ﺍﻷﻣﺛﻠﺔ ﻋﻠﻰ ﺫﻟﻙ ﺍﻳﻭﻥ ﺍﻟﻛﻼﻳﺳﻳﻧﺎﺕ )‪(glycinate ion‬‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫• ﻭ ﺑﺎﻟﻁﺭﻳﻘﺔ ﻧﻔﺳﻬﺎ ﻓﺈﻥ ﺍﻟﻣﻌﻘﺩﺍﺕ ﺛﻧﺎﺋﻳﺔ ﺍﻻﺳﺗﺑﺩﺍﻝ ﺛﻣﺎﻧﻳﺔ ﺍﻷﻭﺟﻪ ‪ octahedral‬ﺗﺗﻭﺍﺟﺩ ﻓﻲ ﺻﻭﺭﺓ ﺍﻟﻣﺟﺎﻭﺭ‪، cis‬ﻭ‬
‫ﺍﻟﻣﺗﻘﺎﺑﻝ ‪ trans‬ﻣﺛﺎﻝ‪ :‬ﺍﻟﻣﻌﻘﺩ ‪ [Co(NH3)4Cl2]Cl‬ﻟﻪ ﺍﻟﺷﺑﻳﻬﻳﻥ ﺍﻟﻬﻧﺩﺳﻳﻳﻥ ﺍﻟﺗﺎﻟﻳﻳﻥ ‪.‬‬
‫‪Cl Cl‬‬

‫‪H3N‬‬ ‫‪Cl H3N‬‬ ‫‪NH3‬‬

‫‪Co Co‬‬

‫‪H3N‬‬ ‫‪NH3‬‬ ‫‪H3N‬‬ ‫‪NH3‬‬

‫‪NH3‬‬ ‫‪Cl‬‬
‫‪cis‬‬ ‫‪trans‬‬

‫)‪(Violet‬‬ ‫)‪(Green‬‬

‫ﻭﻟﻘﺩ ﺗﻡ ﺗﺣﺿﻳﺭ ﻭ ﺗﺷﺧﻳﺹ ﺧﻭﺍﺹ ﻣﺋﺎﺕ ﺍﻟﻣﺭﻛﺑﺎﺕ ﺍﻻﻳﺯﻭﻣﺭﻳﺔ ﻣﻥ ﺃﻧﻭﺍﻉ ]‪[M(AA)2XY] , [MA4YX] ,[M(AA)2X2‬‬
‫]‪,[MA4X2‬‬

‫ﺣﻳﺙ ‪M=Co(III),Cr(III),Rh(III),Ir(III),Pt(IV),Ru(II),Os(II) :‬‬

‫ﻭﻣﻌﺭﻭﻑ ﺃﻳﺿﺎً ﻋﺩﺩ ﻣﻥ ﺍﻻﻳﺯﻭﻣﺭﺍﺕ ﻣﻥ ﻧﻭﻉ ]‪ [MA3X3‬ﻭﻓﻲ ﻫﺫﺍ ﺍﻟﻧﻭﻉ ﻣﻥ ﺍﻟﻣﺭﻛﺑﺎﺕ ﺗﻌﻁﻲ ﺍﻳﺯﻭﻣﺭﻳﻥ ﻫﻧﺩﺳﻳﻳﻥ ﻓﻘﻁ‪ ،‬ﻛﻣﺎ‬
‫ﻓﻲ ﺍﻟﻣﻌﻘﺩ ]‪[Co(NH3)3Cl3‬‬

‫‪Cl Cl‬‬

‫‪H3N‬‬ ‫‪Cl H3N‬‬ ‫‪Cl‬‬
‫‪Co‬‬ ‫‪Co‬‬

‫‪H3N‬‬ ‫‪NH3‬‬ ‫‪H3N Cl‬‬

‫‪Cl‬‬ ‫‪NH3‬‬
‫‪mer‬‬ ‫‪fac‬‬
‫‪ (facial)fac‬ﻭﺟﻬﻳﺎ )‪(trans‬‬
‫‪ (meridional)mer‬ﻣﺣﻭﺭﻳﺎ‪(cis)-‬‬

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‫م‪.‬ﺣﻮراء ﻣﻬﺪي‬ ‫اﻟﻤﺮﺣﻠﺔ اﻟﺜﺎﻟﺜﺔ‬ ‫ﻣﺤﺎﺿﺮات اﻟﻜﻴﻤﻴﺎء اﻟﺘﻨﺎﺳﻘﻴﺔ‬

‫‪ -2‬ﺍﻻﻳﺯﻭﻣﺭﻳﺔ ﺍﻟﻣﻭﻗﻌﻳﺔ ‪ Position isomers‬ﺍﻭ ﺍﻻﻳﺯﻭﻣﺭﺍﺕ ﺍﻟﺗﺭﻛﻳﺑﻳﺔ ‪structural isomers‬‬

‫‪ -:‬ﻭﻫﻲ ﺍﻳﺯﻭﻣﺭﺍﺕ ﻟﻬﺎ ﻧﻔﺱ ﻣﺟﺎﻣﻳﻊ ﺍﻟﺫﺭﺍﺕ ﻭ ﻟﻛﻥ ﺗﺭﺗﻳﺏ ﺍﻷﻭﺍﺻﺭ ﻓﻳﻬﺎ ﻣﺧﺗﻠﻑ ﻓﻣﺛﻼً ﺻﻳﻐﺔ ‪ C2H6O‬ﺗﻣﺛﻝ‬
‫ﺍﻳﺯﻭﻣﺭﻳﻥ ﻣﻥ ﻫﺫﺍ ﺍﻟﻧﻭﻉ ﻭﻫﻣﺎ ﺍﻟﻛﺣﻭﻝ ﺍﻻﺛﻳﻠﻲ ‪ CH3CH2OH‬ﻭ ﺍﻻﻳﺛﺭ ﺍﻟﻣﺛﻳﻠﻲ ‪. CH3-O-CH3‬‬

‫• ﺍﻟﺗﺷﺎﺑﻪ ﺍﻟﺗﺄﻳﻧﻲ‪Ionization isomerism - :‬‬
‫ﻳﻧﺗﺞ ﻋﻧﺩ ﺇﺫﺍﺑﺔ ﻣﻌﻘﺩ ﻣﺎ‪ ،‬ﻭ ﻳﻅﻬﺭ ﻧﺗﻳﺟﺔ ﻟﺗﺑﺎﺩﻝ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺑﻳﻥ ﺃﻳﻭﻥ ﻳﺷﻐﻝ ﺍﺣﺩ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﺩﺍﺧﻝ ﺍﻻﻳﻭﻥ ﺍﻟﻣﻌﻘﺩ‬

‫ﻭ ﺍﻷﻳﻭﻧﺎﺕ ﺧﺎﺭﺟﻪ‪ ،‬ﻓﻳﻛﻭﻥ ﻟﻪ ﻧﻔﺱ ﺍﻟﺻﻳﻐﺔ ﺍﻟﺟﺯﻳﺋﻳﺔ‪ .‬ﻣﺛﺎﻝ‪:‬‬

‫‪ [Co(NH3)5Br]SO4‬ﺃﺣﻣﺭ ﺑﻧﻔﺳﺟﻲ ﺍﻟﺷﺑﻳﻪ ﺍﻷﻳﻭﻧﻲ ﻟﻪ ‪ [Co(NH3)5SO4]Br‬ﺃﺣﻣﺭ‪[Pt(NH3)3Cl]Br .‬‬
‫‪, [Pt(NH3)3Br]Cl‬‬

‫ﻭﺍﻳﺯﻭﻣﺭﺍﺕ ﺍﻟﺗﺄﻳﻥ ﻟﻠﻣﺭﻛﺏ ‪[Co(en)2(NO2)CI]SCN , [Co(en)2(NO2)(SCN)]CI ,[Co(en)2(SCN)CI]NO2‬‬

‫• ﺍﻟﺗﺷﺎﺑﻪ ﺍﻟﺗﻣﻳﻬﻲ‪Hydrated isomerism -:‬‬
‫ﻫﺫﺍ ﺍﻟﺗﺷﺎﺑﻪ ﺣﺎﻟﺔ ﺧﺎﺻﺔ ﻣﻥ ﺗﺷﺎﺑﻪ ﺍﻟﺗﺄﻳﻥ ‪ ،‬ﻭﻓﻲ ﻫﺫﺍ ﺍﻟﻧﻭﻉ ﻳﺗﻡ ﺍﻟﺗﺑﺎﺩﻝ ﺍﻟﺩﺍﺧﻠﻲ ﻟﻠﻣﺫﻳﺏ )ﻭﻫﻭ ﺍﻟﻣﺎء ﻋﺎﺩ ًﺓ( ﺑﻳﻥ‬

‫ﺍﻟﻣﻌﻘﺩ ﻭ ﺑﻘﻳﺔ ﺍﻟﻣﺭﻛﺏ ﻣﺛﺎﻝ‪:‬‬

‫‪ [Cr(H2O)6]Cl3‬ﺑﻧﻔﺳﺟﻲ ‪ [CrCl(H2O)5]Cl2.H2O ،‬ﺃﺧﺿﺭ‪ [CrCl2(H2O)4]Cl.(H2O)2 ،‬ﺃﺧﺿﺭ‪ .‬ﻭ‬
‫ﻳﻣﻛﻥ ﺗﻌﻳﻳﻥ ﻧﺳﺑﺔ ﺃﻳﻭﻥ ﺍﻟﻛﻠﻭﺭﻳﺩ ﺍﻟﺫﻱ ﺳﻳﺗﺭﺳﺏ ﺑﻭﺍﺳﻁﺔ ﻧﺗﺭﺍﺕ ﺍﻟﻔﺿﺔ‪.‬‬

‫• ﺍﻟﺗﺷﺎﺑﻪ ﺍﻹﺭﺗﺑﺎﻁﻲ‪Linkage isomerism - :‬‬
‫ﺗﺣﺗﻭﻱ ﺑﻌﺽ ﺍﻟﻠﻳﻛﺎﻧﺩﺍﺕ ﻋﻠﻰ ﺃﻛﺛﺭ ﻣﻥ ﺫﺭﺓ ﻳﻣﻛﻥ ﻟﻬﺎ ﺃﻥ ﺗﺷﺎﺭﻙ ﺑﺯﻭﺝ ﻣﻥ ﺍﻹﻟﻛﺗﺭﻭﻧﺎﺕ‪ ،‬ﻣﺛﺎﻝ‪ :‬ﺃﻳﻭﻥ ‾‪NO2‬‬
‫‪ ،‬ﺇﺫ ﺃﻥ ﻛﻼ ﻣﻥ ﺫﺭﺓ ﺍﻟﻧﻳﺗﺭﻭﺟﻳﻥ ﻭ ﺍﻷﻭﻛﺳﺟﻳﻥ ﻳﻣﻛﻥ ﻟﻬﺎ ﺃﻥ ﺗﺷﺎﺭﻙ ﺑﺯﻭﺝ ﻣﻥ ﺍﻹﻟﻛﺗﺭﻭﻧﺎﺕ‪ .‬ﻓﺈﺫﺍ ﺍﺭﺗﺑﻁﺕ ﻣﻥ‬
‫ﺧﻼﻝ ﺫﺭﺓ ﺍﻟﻧﻳﺗﺭﻭﺟﻳﻥ ﻓﻳﺳﻣﻰ ﻧﺎﻳﺗﺭﻭ ‪ nitro‬ﺃﻭ ﺃﻥ ﺗﺭﺗﺑﻁ ﻣﻥ ﺧﻼﻝ ﺫﺭﺓ ﺍﻷﻭﻛﺳﺟﻳﻥ ﻓﻳﺳﻣﻰ ﻧﺎﻳﺗﺭﻳﺗﻭ‬
‫‪ ، nitrite‬ﻛﻣﺎ ﻓﻲ ﺷﺑﻳﻬﻲ ﺍﻟﻣﻌﻘﺩ ﺍﻟﻧﺎﻳﺗﺭﻭ ‪ [Co(NH3)5NO2]Cl2‬ﻻﺭﺗﺑﺎﻁﻪ ﻣﻥ ﺧﻼﻝ ﺫﺭﺓ ﺍﻟﻧﻳﺗﺭﻭﺟﻳﻥ‬
‫)ﺣﻳﺙ ﺗﻬﺏ ﻟﻠﺫﺭﺓ ﺍﻟﻣﺭﻛﺯﻳﺔ ﺯﻭﺝ ﺍﻹﻟﻛﺗﺭﻭﻧﺎﺕ ﻣﻥ ﺧﻼﻝ ﺫﺭﺓ ﺍﻟﻧﻳﺗﺭﻭﺟﻳﻥ(‪ .‬ﻭ ﺍﻟﻣﻌﻘﺩ‬
‫ﺍﻟﻧﺎﻳﺗﺭﻳﺗﻭ ‪ [Co(NH3)5ONO]Cl2‬ﻻﺭﺗﺑﺎﻁﻪ ﻣﻥ ﺧﻼﻝ ﺫﺭﺓ ﺍﻷﻛﺳﺟﻳﻥ )ﺣﻳﺙ ﺗﻬﺏ ﻟﻠﺫﺭﺓ ﺍﻟﻣﺭﻛﺯﻳﺔ ﺯﻭﺝ‬
‫ﺍﻹﻟﻛﺗﺭﻭﻧﺎﺕ ﻣﻥ ﺧﻼﻝ ﺫﺭﺓ ﺍﻷﻛﺳﺟﻳﻥ(‪ .‬ﻭ ﻳﻣﻛﻥ ﺗﻭﻗﻊ ﻫﺫﺍ ﺍﻟﻧﻭﻉ ﻣﻥ ﺍﻻﻳﺯﻭﻣﺭﻳﺔ ﻣﻊ ﻟﻳﻛﺎﻧﺩﺍﺕ ﺃﺧﺭﻯ‪ ،‬ﻣﺛﻝ‬
‫‾‪ SCN‬ﺣﻳﺙ ﻳﺭﺗﺑﻁ ﻣﻥ ﺧﻼﻝ ﺫﺭﺓ ﺍﻟﻛﺑﺭﻳﺕ ﻓﻳﺳﻣﻰ ﺛﺎﻳﻭﺳﻳﺎﻧﺎﺗﻭ ‪ thiocyanato‬ﺃﻭ ﻣﻥ ﺧﻼﻝ ﺫﺭﺓ‬

‫ﺍﻟﻧﻳﺗﺭﻭﺟﻳﻥ ﻓﻳﺳﻣﻰ ﺍﻳﺯﻭﺛﺎﻳﻭﺳﻳﺎﻧﺎﺗﻭ ‪. isothiocyanato‬‬

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