Ca2Ta2O7
Grey I E, Mumme W G, Ness T J, Roth R S, Smith K L
Journal of Solid State Chemistry 174 (2003) 285-295
Structural relations between weberite and zirconolite polytypes - refinements
of doped 3T and 4M Ca2Ta2O7 and 3T CaZrTi2O7
Sample: T = 123 K, 3T weberite-type structure
_database_code_amcsd 0014035
7.356 7.356 18.116 90 90 120 P3_121
atom      x      y      z  occ  Uiso
CaM1  .8412      0    1/3 .970 .0080
NdM1  .8412      0    1/3 .030 .0080
TaM2 .31000      0    1/3      .0052
CaM3  .1594  .6475  .0038 .968 .0111
NdM3  .1594  .6475  .0038 .032 .0111
TaM4 .32910      0    5/6  .92 .0049
ZrM4 .32910      0    5/6  .06 .0049
NdM4 .32910      0    5/6  .02 .0049
CaM5  .8333      0    5/6      .0115
TaM6  .5019 .33232 .16285  .93 .0042
ZrM6  .5019 .33232 .16285  .05 .0042
NdM6  .5019 .33232 .16285  .02 .0042
O1     .557   .606  .1994       .015
O2     .957   .802  .0484       .012
O3     .547   .406  .0574       .011
O4     .201   .223  .1488       .016
O5     .542   .789  .0646       .014
O6     .963   .312  .0572       .010
O7     .198   .634  .1519       .013