Calcite
Maslen E N, Streltsov V A, Streltsova N R, Ishizawa N
Acta Crystallographica B51 (1995) 929-939
Electron density and optical anisotropy in rhombohedral carbonates.
III. Synchrotron X-ray studies of CaCO3, MgCO3 and MnCO3
_database_code_amcsd 0009890
4.988 4.988 17.068 90 90 120 R-3c
atom      x y   z U(1,1) U(2,2) U(3,3) U(1,2)  U(1,3)  U(2,3)
Ca        0 0   0 .00988 .00988 .00932 .00494       0       0
C         0 0 .25 .00834 .00834  .0108 .00417       0       0
O    .25700 0 .25 .01129  .0220  .0202  .0110 -.00424 -.00848