Crystal Structures and Lattice - ASM International

Crystal Structures and Cell Parameters of
Allotropes of the Chemical Elements

The crystal structures of the allotropic forms of the metallic elements are presented in terms of the Pearson symbol, space group, Strukturbericht designation, and prototype of the structure. The temperatures of the
phase transformations are listed in degrees Celsius and the pressures are in GPa. A consistent nomenclature is used, whereby all allotropes are labeled by Greek letters. The lattice parameters of the unit cells are given
in nanometers (nm) and are considered to be accurate to ±2 in the last reported digit.
This compilation is restricted to changes in crystal structure that occur as a result of a change in temperature or pressure. Low-temperature structures are included for the diatomic and rare gases, which show many
similarities with respect to the metallic elements.
This compilation updates and supersedes previous compilations published in the Bulletin of Alloy Phase Diagrams.
Most of the data given below are the same as in the first edition. However, occasionally changes were made when updated information was supplied by a category editor, or by present volume editors. The reader's
attention is drawn to the fact that there may differences between values quoted below and similar values given in another table in this edition that has been reproduced from another source. For example, the allotropic
transformation temperatures of Mn may differ by as much as 23 °C, etc.

Cell parameters, nm

Struktur-

bericht Pearson Space Comment,c/a, or
α or β
Element Common Temperature,°C Pressure,GPa designation Prototype symbol group abc
phase name ...
25 atm A1 Cu cF4 Fm 3 m 0.5311 ... ... ...
(Ac) Ac 25 atm A1 Cu cF4 Fm 3 m 0.40857 ... ... ...
25 atm A1 Cu cF4 Fm 3 m 0.40496 ... ... 1.6331
(Ag) Ag 25 20.5 A3 Mg hP2 P63/mmc 0.2693 ... 0.4398 2 x 1.621
25 atm A3´ Nd hP4 P63/mmc 0.34681 ... 1.1241 ...
(Al) αAl >769 atm A1 Cu cF4 Fm 3 m 0.4894 ... ... ...
βAl >1077 atm A2 W cI2 Im 3 m ? ... ... ...
(Al) hp αAm 25 >15 A20 U oS4 Cmcm 0.3063 0.5968 0.5169
(Am) rt βAm
(Am) ht1 γAm
δAm
(Am) ht2

(Am) hp

ASM Alloy Phase Diagrams Center, P. Villars, editor-in-chief; H. Okamoto and K. Cenzual, section editors;
www.asminternational.org/AsmEnterprise/APD, ASM International, Materials Park, OH, USA, 2007
© ASM International 2007. All Rights Reserved.

Cell parameters, nm

Element Common Temperature,°C Pressure,GPa Struktur- Prototype Pearson Space abc Comment,c/a, or
phase name bericht symbol group α or β
<-189.2 atm designation Cu 0.53109 ... ...
(Ar) αAr 25 atm As cF4 Fm 3 m 0.41319 ... ... ...
As 25 atm A1 Cu hR6 R3m 0.40782 ... ... α = 54.12°
(As) 25 atm A7 B cF4 Fm 3 m 1.017 ... ... ...
Au A1 hR423 R3m α = 65.12°
(Au) 25 atm ... W 0.50227 ... ...
βB 25 >5.33 Mg cI2 Im 3 m ...
(B) 25 >23 A2 ... hP2 P63/mmc 0.3901 ... 0.6154 1.5775
rhom1 αBa 25 atm A3 Mg ? ? ... ... ... ...
(Ba) βBa >1270 atm ... W hP2 P63/mmc 0.22859 ... 0.35845 1.5681
γBa 25 >28.3 A3 ... cI2 Im 3 m 0.25515 ... ... ...
(Ba) hp1 αBe 25 atm A2 As hP* ... 0.7893
(Ba) hp2 βBe 25 >2.6 ... βBi hR6 R3m 0.4328 ... 0.3416 α = 57.23°
(Be) rt BeII 25 >3.0 A7 ... mS4 C12/m1 0.47460 ... ... β = 110.33°
(Be) ht αBi 25 >4.3 ... ... mP4 P121/m1 β = 85.33°
βBi 25 >9.0 ... W ? ? 0.6674 0.6117 0.3304 ...
(Be) hp γBi 25 atm ... Nd cI2 Im 3 m 0.665 0.420 0.465 ...
(Bi) δBi >977 atm A2 Cu hP4 P63/mmc ... ... ... 2 x 1.620
ζBi <-7.25 atm A3´ [I2] cF4 Fm 3 m 0.3800 ... ... ...
(Bi) hp1 αBk 25 atm A1 C oS8 Cmce ...
(Bi) hp2 βBk 25 >60 A14 C hP4 P63/mmc 0.3416 ... 1.1069 2.7258
(Bi) hp3 Br A9 cF8 Fd 3 m 0.4997 ... ... ...
(Bi) hp4 C(graphite) A4
C(diamond) 0.668 0.449 0.874
(Bk) rt 0.24612 ... 0.6709
(Bk) ht 0.35669 ... ...

([Br2])
(C) gra
(C) dia

ASM Alloy Phase Diagrams Center, P. Villars, editor-in-chief; H. Okamoto and K. Cenzual, section editors;
www.asminternational.org/AsmEnterprise/APD, ASM International, Materials Park, OH, USA, 2007
© ASM International 2007. All Rights Reserved.

Cell parameters, nm

Element Common Temperature,°C Struktur- Prototype Pearson Space abc Comment,c/a, or
phase name bericht symbol group α or β
25 Pressure,GPa designation Cu
(Ca) rt αCa >443 W cF4 Fm 3 m ...
25 atm A1 Mg cI2 Im 3 m 0.55884 ... ... ...
(Ca) ht βCa 25 Mg hP2 P63/mmc ...
<-177 atm A2 Cu hP2 P63/mmc 0.4480 ... ... 1.8862
(Ca) stab γCa 25 >1.5 A3 Nd cF4 Fm 3 m ... ... ... ...
(Cd) Cd >61 atm A3 Cu hP4 P63/mmc 0.29793 ... 0.56196 2 x 1.611
(Ce) ht1 αCe >726 atm A1 W cF4 Fm 3 m 0.485 ... ... ...
25 U cI2 Im 3 m ...
(Ce) rt βCe 25 atm A3´ Nd oS4 Cmcm 0.36810 ... 1.1857 ...
(Ce) ht1 γCe >590 atm A1 Cu hP4 P63/mmc 0.51610 ... ... 2 x 1.625
<-100.97 [I2] cF4 Fm 3 m ...
(Ce) ht2 δCe 25 atm A2 Nd oS8 Cmce 0.412 ... ... ...
>1277 Cu hP4 P63/mmc 2 x 1.621
(Ce) hp α´Ce 25 >5.4 A20 Mg cF4 Fm 3 m 0.3049 0.5998 0.5215 ...
(Cf) rt αCf >422 atm A3´ Cu hP2 P63/mmc 0.339 ... 1.1015 1.6228
(Cf) ht βCf 25 atm A1 W cF4 Fm 3 m ? ... ... ...
25 Cr cI2 Im 3 m ...
([Cl2]) Cl 25 atm A14 W tI2 I4/mmm 0.624 0.448 0.826 1.002
(Cm) rt αCm 25 atm A3´ Cu cI2 0.3496 ... 1.1331 ...
(Cm) ht βCm 25 atm A1 Cu cF4 Im 3 m 0.4382 ... ... ...
atm A3 cF4 Fm 3 m 0.25071 ... 0.40686 ...
(Co) rt εCo atm A1 Fm 3 m 0.35447 ... ...
(Co) ht αCo
atm A2 0.28848 ... ...
(Cr) αCr hp ... 0.2882 ... 0.2887
atm A2 0.6141 ... ...
(Cr) hp α´Cr
(Cs) αCs >2.37 A1 0.6465 ... ...
>4.22 A1 0.5800 ... ...
(Cs) hp1 βCs

(Cs) hp2 β´Cs

ASM Alloy Phase Diagrams Center, P. Villars, editor-in-chief; H. Okamoto and K. Cenzual, section editors;
www.asminternational.org/AsmEnterprise/APD, ASM International, Materials Park, OH, USA, 2007
© ASM International 2007. All Rights Reserved.

Cell parameters, nm

Element Common Temperature,°C Struktur- Prototype Pearson Space abc Comment,c/a, or
phase name bericht symbol group α or β
25 Pressure,GPa designation ...
(Cs) hp3 γCs 25 Cu ? ... ...
(Cu) Cu <-187 >4.27 ... U cF4 ... ... ... ...
25 atm A1 Mg oS4 Fm 3 m 0.36146 ... ... ...
(Dy) lt α´Dy >1381 W hP2 Cmcm 1.5732
(Dy) rt αDy 25 atm ... CdCl2 cI2 P63/mmc 0.3595 0.6184 0.5678 ...
(Dy) ht βDy 25 atm A3 Mg hR9 Im 3 m 0.35915 ... 0.56501 4.5 x 1.606
25 atm A2 Nd hP2 R3m (0.398) ... ... 1.5692
(Dy) hp γDy ? Cu hP4 P63/mmc ...
25 >7.5 C19 W cF4 P63/mmc 0.3436 ... 2.483 ...
(Er) Er <-227.60 [F2] cI2 Fm 3 m ...
(Es) αEs <-219.67 atm A3 [F2] mS8 Im 3 m 0.35592 ... 0.55850 β = 102.17°
(Es?) βEs 25 atm A3´ W cP64 C12/c1 ? ... ... ...
>912 atm A1 Cu cI2 ? ... ... ...
(Eu) Eu >1394 W cF4 Pm 3 n ...
25 atm A2 Mg cI2 Im 3 m 0.45827 ... ... ...
([F2]) lt2 αF 25 Ga hP2 Fm 3 m 1.603
([F2]) lt1 βF 25 atm ... In oS8 Im 3 m 0.550 0.338 0.728 ...
(Fe) rt -53 atm ... Ga tI2 P63/mmc 0.667 ... ... 1.588
αFe 25 Mg oS40 Cmce ...
(Fe) ht >1235 atm A2 W hP2 I4/mmm 0.28665 ... ... 1.5910
γFe cI2 Cmcm ...
(Fe) rt atm A1 P63/mmc 0.36467 ... ...
δFe Im 3 m
(Fe) hp atm A2 0.29315 ... ...
(Ga) εFe
(Ga) lt αGa >13 A3 0.2468 ... 0.396
(Ga) hp βGa atm A11 0.45186 0.76570 0.45258
(Gd) rt γGa >1.2 A6 0.2808 ... 0.4458
(Gd) ht αGd >3.0 ... 1.0593 1.3523 0.5203
βGd atm A3 0.36336 ... 0.57810
atm A2 0.406 ... ...

ASM Alloy Phase Diagrams Center, P. Villars, editor-in-chief; H. Okamoto and K. Cenzual, section editors;
www.asminternational.org/AsmEnterprise/APD, ASM International, Materials Park, OH, USA, 2007
© ASM International 2007. All Rights Reserved.

Cell parameters, nm

Element Common Temperature,°C Struktur- Prototype Pearson Space abc Comment,c/a, or
phase name bericht symbol group α or β
25 Pressure,GPa designation Sm
(Gd) hp γGd 25 C hR9 R3m 4.5 x 1.60
25 >3.0 C19 Sn cF8 Fd 3 m 0.361 ... 2.603 ...
(Ge) αGe 25 Ge tI4 I41/amd 0.551
LT atm A4 Si tP12 P41212 0.56574 ... ... 1.18
(Ge) hp1 βGe <-271.9 Cu cI16 ...
(Ge) hp2 γGe <-259.34 >12 A5 Mg cF4 Ia 3 0.4884 ... 0.2692 ...
(Ge) hp3 δGe -269.67 >12 → atm ... Mg hP2 Fm 3 m 0.593 ... 0.698 1.632
-269.2 >12 ... Mg hP2 P63/mmc 0.692 ... ... 1.634
([H2]) lt1 αH 25 Mg hP2 P63/mmc 1.597
([H2]) >1743 atm A1 W hP2 P63/mmc 0.5338 ... ... 1.5811
(He) lt2 βH <-38.836 Hg cI2 P63/mmc ...
(He) lt1 He3 <-194 atm A3 Hg hR3 0.3776 ... 0.6162 α = 70.53°
(Hf) rt He4 25 0.163 A3 Mg tI2 Im 3 m 0.3501 ... 0.5721 0.707
(Hf) ht αHf 25 0.129 A3 Sm hP2 R3m 0.3470 ... 0.5540 1.5702
βHf 25 atm A3 [I2] hR9 I4/mmm 0.31946 ... 0.50510 4.5 x 1.63
(Hg) 25 atm A2 In oS8 P63/mmc 0.3610 ... ... ...
αHg 25 Cu tI2 1.5210
(Hg) hp 25 atm A10 W cF4 R3m 0.3005 ... ... ...
(Ho) βHg <-157.385 Cu cI2 Cmce ...
(Ho) hp αHo 25 hp ... Nd cF4 I4/mmm 0.3995 ... 0.2825 ...
βHo atm A3 hP4 Fm 3 m 0.35778 ... 0.56178 2 x 1.6125
([I2]) >7.5 C19 Im 3 m 0.334 ... 2.45
(In) I Fm 3 m
(Ir) In atm A14 P63/mmc 0.72697 0.47903 0.97942
Ir atm A6 0.3253 ... 0.49470
(K) atm A1 0.38392 ... ...
K
(Kr) atm A2 0.5321 ... ...
Kr
(La) rt atm A1 0.5810 ... ...
αLa
atm A3´ 0.37740 ... 1.2171

ASM Alloy Phase Diagrams Center, P. Villars, editor-in-chief; H. Okamoto and K. Cenzual, section editors;
www.asminternational.org/AsmEnterprise/APD, ASM International, Materials Park, OH, USA, 2007
© ASM International 2007. All Rights Reserved.

Cell parameters, nm

Element Common Temperature,°C Struktur- Prototype Pearson Space ab c Comment,c/a, or
phase name bericht symbol group α or β
>310 Pressure,GPa designation Cu 0.5303 ... ...
(La) ht1 βLa >865 W cF4 Fm 3 m ... ...
25 atm A1 Cu cI2 Im 3 m 0.426 ... ... ...
(La) ht2 γLa <-193 atm A2 Mg cF4 Fm 3 m 0.517 ... 0.5093 ...
25 >2.0 A1 W hP2 P63/mmc ... 1.637
(La) hp β´La 25 atm A3 Mg cI2 Im 3 m 0.3111 ... 0.55494 ...
25 atm A2 Mg hP2 P63/mmc 0.35093 ... 0.52107 1.5832
(Li) lt αLi 25 atm A3 Mn hP2 P63/mmc 0.35052 ... ... 1.6236
(Li) rt βLi >727 atm A3 Mn cI58 I 4 3m 0.32094 ... ... ...
Lu >1100 atm A12 Cu cP20 P4132 0.89126 ... ... ...
(Lu) Mg >1138 atm A13 W cF4 Fm 3 m 0.63152 ... ... ...
(Mg) αMn 25 atm A1 W cI2 Im 3 m 0.3860 ... ... ...
(Mn) rt βMn <-237.54 atm A2 [N2] cI2 Im 3 m ... ...
(Mn) ht1 γMn <-210.004 atm A2 [N2] cP8 P213 0.3080 ... 0.6604 ...
(Mn) ht3 <-253 atm ... [N2] hP24 P63/mmc 0.5109 1.631
δMn <-233 atm ... Mg tP4 P42/mnm 0.31470 ... 0.6154 1.291
(Mn) ht4 25 >3.3 ... W hP2 P63/mmc ... 1.634
Mo 25 atm A3 W cI2 Im 3 m 0.5661 ... ... ...
(Mo) 25 atm A2 Nd cI2 Im 3 m 0.4050 ... 1.17966 ...
αN >863 atm A2 W hP4 P63/mmc 0.3957 ... ... 2 x 1.6124
([N2]) lt2 βN 25 atm A3´ Cu cI2 Im 3 m 0.3767 ... ... ...
([N2]) lt1 γN atm A2 cF4 Fm 3 m 0.42906 ... ...
([N2]) hp αNa >5.0 A1
(Na) lt βNa 0.33004 ...
(Na) rt
Nb 0.36582 ...
(Nb) 0.413 ...
αNd
(Nd) rt βNd 0.480 ...
(Nd) ht
γNd
(Nd) hp

ASM Alloy Phase Diagrams Center, P. Villars, editor-in-chief; H. Okamoto and K. Cenzual, section editors;
www.asminternational.org/AsmEnterprise/APD, ASM International, Materials Park, OH, USA, 2007
© ASM International 2007. All Rights Reserved.

Cell parameters, nm

Element Common Temperature,°C Struktur- Prototype Pearson Space abc Comment,c/a, or
phase name bericht symbol group α or β
<-248.587 Pressure,GPa designation Cu
(Ne) Ne 25 Cu cF4 Fm 3 m ...
25 atm A1 Np cF4 Fm 3 m 0.4462 ... ... ...
(Ni) Ni >280 Np oP8 Pnma ...
>576 atm A1 W tP4 P4/nmm 0.35240 ... ... 0.694
(Np) rt αNp <-249.283 [O2] cI2 ...
(Np) ht1 βNp <-229.349 atm Ac [O2] mS4 Im 3 m 0.6663 0.4723 0.4887 β = 132.53°
(Np) ht2 γNp <-218.789 atm Ad [O2] hR6 C12/m1 0.4883 ... 0.3389 α = 46.27°
25 atm A2 Mg cP64 0.352 ... ... ...
([O2]) lt3 αO 25 Mn hP2 R3m 1.5800
([O2]) βO 25 atm ... P cI58 Pm 3 n 0.5403 0.3429 0.5086 ...
([O2]) lt1 25 atm ... Pa oS8 P63/mmc 0.4210 ... ... ...
(Os) γO >1170 W tI2 I 4 3m 0.825
(P) whi rt 25 atm ... Cu cI2 Cmce 0.683 ... ... ...
(P) bla Os 25 Mg cF4 I4/mmm ...
(Pa) rt αP(white) 25 atm A3 Cu hP2 0.27341 ... 0.43198 1.650
(Pa) ht P(black) 25 atm ... Nd cF4 Im 3 m 0.718 ... ... ...
αPa 25 atm A17 Po hP4 Fm 3 m 0.33136 1.0478 0.43763 2 x 1.60
(Pb) βPa >54 atm Aa Po cP1 P63/mmc 0.3921 ... 0.3235 ...
25 atm A2 Nd hR3 Fm 3 m 0.381 ... ... α = 98.08°
(Pb) hp αPb >795 W hP4 P63/mmc 2 x 1.6111
(Pd) atm A1 cI2 Pm 3 m 0.49502 ... ... ...
βPb R3m
(Pm) rt Pd >10.3 A3 P63/mmc 0.3265 ... 0.5387
(Po) rt atm A1 Im 3 m 0.38903 ... ...
αPm
(Po) ht αPo atm A3´ 0.365 ... 1.165
(Pr) rt atm Ah 0.3366 ... ...
(Pr) ht βPo Ai
αPr atm A3´ 0.3373 ... ...
βPr atm A2 0.36721 ... 1.18326
atm 0.413 ... ...

ASM Alloy Phase Diagrams Center, P. Villars, editor-in-chief; H. Okamoto and K. Cenzual, section editors;
www.asminternational.org/AsmEnterprise/APD, ASM International, Materials Park, OH, USA, 2007
© ASM International 2007. All Rights Reserved.

Cell parameters, nm

Element Common Temperature,°C Struktur- Prototype Pearson Space abc Comment,c/a, or
phase name bericht symbol group α or β
25 Pressure,GPa designation Cu
(Pr) hp γPr 25 Cu cF4 Fm 3 m ...
25 >4.0 A1 Pu cF4 Fm 3 m 0.488 ... ... ...
(Pt) Pt >125 Pu mP16 P121/m1
>215 atm A1 Pu mS34 C12/m1 0.39236 ... ... β = 101.97°
(Pu) rt αPu >320 Cu oF8 Fddd β = 92.13°
(Pu) ht1 βPu >463 atm ... In cF4 0.6183 0.4822 1.0963 ...
(Pu) ht2 γPu >483 atm ... W tI2 Fm 3 m 0.9284 1.0463 0.7859 ...
(Pu) ht3 δPu 25 atm ... W cI2 I4/mmm 0.31587 0.57682 1.0162 1.3418
25 atm A1 W cI2 0.46371 ... ... ...
(Pu) ht4 δ´Pu 25 ... cI2 Im 3 m ...
(Pu) ht5 εPu 25 atm A6 ... ? Im 3 m 0.33261 ... 0.44630 ...
25 atm A2 Mg ? Im 3 m 0.36343 ... ... ...
(Ra) Ra 25 Cu hP2 ... ...
25 atm A2 Mg cF4 ... 0.5148 ... ... 1.6145
(Rb) αRb 25 S hP2 P63/mmc ...
>95.5 atm A2 S oF128 Fm 3 m 0.5705 ... ... 1.5824
(Rb) hp1 βRb 25 As mP64 P63/mmc ...
(Rb) hp2 γRb 25 >1.08 ... Po hR6 Fddd ... ... ... β = 96.7°
(Re) Re 25 >2.05 ... ... cP1 P21/c1 ... ... ... α = 57.11°
(Rh) Rh 25 atm A3 Mg mP3 0.27609 ... 0.4458 ...
atm A1 hP2 R3m 0.38032 ... ...
(Ru) Ru Pm 3 m β = 86.0°
(S) 8αrt αS atm A3 ? 0.27058 ... 0.42816 1.5921
(S) 8βht βS atm A16 P63/mmc 1.0464 1.28660 2.44860
(Sb) αSb atm ... 1.102 1.096 1.090
atm A7 0.45067 ... ...
(Sb) hp1 βSb
>5.0 Ah 0.2992 ... ...
(Sb) hp2 δSb ...
(Sc) rt αSc >14.0 A3 0.556 0.404 0.422
atm 0.33088 ... 0.52680

ASM Alloy Phase Diagrams Center, P. Villars, editor-in-chief; H. Okamoto and K. Cenzual, section editors;
www.asminternational.org/AsmEnterprise/APD, ASM International, Materials Park, OH, USA, 2007
© ASM International 2007. All Rights Reserved.

Cell parameters, nm

Element Common Temperature,°C Struktur- Prototype Pearson Space abc Comment,c/a, or
phase name bericht symbol group α or β
>1337 Pressure,GPa designation W
(Sc) ht βSc 25 Se cI2 Im 3 m ...
25 atm A2 C hP3 P3121 0.373 ... ... 1.1346
(Se) γSe 25 A8 Sn cF8 Fd 3 m 0.43659 ... 0.49537 ...
(Si) αSi 25 atm A4 Si tI4 I41/amd 0.54306 ... ... 0.552
25 atm A5 Nd cI16 Ia 3 0.4686 ... 0.2585 ...
(Si) hp1 βSi 25 ... Sm hP4 P63/mmc 0.6636 ... ... 1.653
(Si) hp2 γSi >734 >9.5 A3´ Mg hR9 R3m 0.380 ... 0.628 4.5 x 1.6048
>922 >16.0 C19 W hP2 P63/mmc 0.36290 ... 2.6207 1.5956
(Si) hp3 δSi 25 A3 La cI2 Im 3 m 0.36630 ... 0.58448 ...
(Sm) rt αSm <13 >16 → atm A2 C hP4 P63/mmc ? ... ... 2 x 1.611
25 atm A3´ Sn cF8 Fd 3 m 0.3618 ... 1.166 ...
(Sm) ht1 βSm 25 A4 Pa tI4 I41/amd 0.64892 ... ... 0.5456
(Sm) ht2 γSm 25 atm A5 Cu tI2 I4/mmm 0.58318 ... 0.31818 0.91
>547 atm ... W cF4 0.370 ... 0.337 ...
(Sm) hp δSm 25 A1 W cI2 Fm 3 m 0.6084 ... ... ...
(Sn) lt αSn 25 >4.0 A2 W cI2 Im 3 m 0.487 ... ... ...
<-53 atm A2 Dy cI2 Im 3 m 0.4437 ... ... ...
(Sn) rt βSn 25 atm A2 Mg oS4 Im 3 m 0.33030 ... ... ...
(Sn) hp γSn >1289 >9.0 ... W hP2 Cmcm 0.3605 0.6244 0.5706 1.5800
(Sr) rt αSr 25 atm A3 Sm cI2 P63/mmc 0.36055 ... 0.56966 ...
atm A2 hR9 Im 3 m (0.402) ... ... 4.5 x 1.60
(Sr) ht βSr C19 R3m 0.341 ... 2.45
>3.5
(Sr) hp β´Sr
atm
(Ta) Ta
atm
(Tb) lt αTb atm
(Tb) rt α´Tb atm
(Tb) ht βTb >6.0

(Tb) hp γTb

ASM Alloy Phase Diagrams Center, P. Villars, editor-in-chief; H. Okamoto and K. Cenzual, section editors;
www.asminternational.org/AsmEnterprise/APD, ASM International, Materials Park, OH, USA, 2007
© ASM International 2007. All Rights Reserved.

Cell parameters, nm

Element Common Temperature,°C Struktur- Prototype Pearson Space abc Comment,c/a, or
phase name bericht symbol group α or β
25 Pressure,GPa designation Se
(Te) αTe 25 As hP3 P3121 1.3298
(Te) hp1 βTe 25 atm A8 Po hR6 R3m 0.44566 ... 0.59264 α = 53.30°
25 >2.0 A7 Cu hR3 R3m 0.469 ... ... α = 103.3°
(Te) hp2 γTe >1360 >7.0 W cF4 Fm 3 m ...
25 atm Ai Mg cI2 Im 3 m 0.3002 ... ... ...
(Th) rt αTh >882 atm A1 W hP2 P63/mmc 1.5873
25 atm A2 Ti cI2 Im 3 m 0.50842 ... ... ...
(Th) ht βTh 25 atm A3 Mg hP3 P6/mmm 0.6082
αTi >230 A2 W hP2 P63/mmc 0.411 ... ... 1.5983
(Ti) rt βTi 25 hp → atm ... Cu cI2 Im 3 m ...
(Ti) ht 25 atm A3 Mg cF4 Fm 3 m 0.29506 ... 0.46835 ...
ωTi 25 atm A2 U hP2 P63/mmc 0.33065 ... ... 1.5700
(Ti) hp1 αTl >668 hp A1 U oS4 Cmcm ...
(Tl) rt βTl >776 atm A3 W tP30 P42/mnm 0.4625 ... 0.2813 0.526
(Tl) ht 25 atm A20 W cI2 Im 3 m 0.34566 ... 0.55248 ...
γTl 25 atm Ab W cI2 Im 3 m 0.3879 ... ... ...
(Tl) hp Tm <-111.758 atm A2 Cu cI2 Im 3 m ...
αU 25 atm A2 Mg cF4 Fm 3 m ? ... ... ...
(Tm) βU >1478 atm A2 W hP2 P63/mmc 1.5711
(U) rt γU <-3 atm A1 Mg cI2 Im 3 m 0.35375 ... 0.55540 ...
(U) ht1 V atm A3 hP2 P63/mmc 0.28537 0.58695 0.49548 1.6459
(U) ht2 atm A2 1.0759 ... 0.5656
W atm A3 0.3524 ... ...
(V)
Xe 0.30240 ... ...
(W)
αY 0.31652 ... ...
(Xe) βY
0.6350 ... ...
(Y) rt αYb
(Y) ht 0.36482 ... 0.57318
(0.407) ... ...
(Yb) stab
0.38799 ... 0.63859

ASM Alloy Phase Diagrams Center, P. Villars, editor-in-chief; H. Okamoto and K. Cenzual, section editors;
www.asminternational.org/AsmEnterprise/APD, ASM International, Materials Park, OH, USA, 2007
© ASM International 2007. All Rights Reserved.

Cell parameters, nm

Element Common Temperature,°C Pressure,GPa Struktur- Prototype Pearson Space ab c Comment,c/a, or
bericht symbol group α or β
phase name atm designation Cu ...
atm W cF4 Fm 3 m ... ...
(Yb) rt βYb 25 atm A1 Mg cI2 Im 3 m 0.54848 ... 0.51475 ...
atm A2 W hP2 P63/mmc ... 1.5929
(Yb) ht γYb >795 hp → atm A3 ωTi cI2 Im3m 0.444 ... 0.3109 ...
A2 hP2 P6/mmm 0.32316 ... 0.617
(Zn) αZr 25 ... 0.36090 ...
0.5036 ...
(Zr) ht βZr >863

(Zr) rt ωZr 25

Note: Values in parentheses are estimated.

ASM Alloy Phase Diagrams Center, P. Villars, editor-in-chief; H. Okamoto and K. Cenzual, section editors;
www.asminternational.org/AsmEnterprise/APD, ASM International, Materials Park, OH, USA, 2007
© ASM International 2007. All Rights Reserved.