Calciotantite
Yamnova N A, Pushcharovsky D Yu, Voloshin A V
Soviet Physics Crystallography 33 (1988) 498-499
Identity of ungursaite with calciotantite and synthetic CaTa4O11
Locality: Kola Peninsula, Russia
Note: displacement parameters taken from ICSD
_database_code_amcsd 0015587
6.245 6.245 12.323 90 90 120 P6_322
atom      x     y     z  occ Biso  B(1,1)  B(2,2)  B(3,3)  B(1,2)   B(1,3)   B(2,3)
Ca      1/3   2/3   .75  .94  .35 .002735 .002735 .000659 .001368        0        0
Na      1/3   2/3   .75  .06  .35 .002735 .002735 .000659 .001368        0        0
Ta1  .35897     0     0      .186 .002222 .000598 .000313 .000342 -.000188 -.000075
Ta2     1/3   2/3   .25  .86  .22 .001880 .001880 .000362 .000940        0        0
Nb2     1/3   2/3   .25  .13  .22 .001880 .001880 .000362 .000940        0        0
O1     .375  .943 .1554 .995   .4 .005128 .004274 .000329 .003419  .000750  .001125
O2     .757     0     0        .1 .001709 .000000 .000329 .000000  .003376  .001500
O3      1/3   2/3 .9663        .1 .000855 .000855 .000000 .000513        0        0