Columbite-(Fe)
Tarantino S C, Zema M
American Mineralogist 90 (2005) 1291-1300
Mixing and ordering behavior in manganocolumbite-ferrocolumbite solid solution:
A single-crystal X-ray diffraction study
Sample: BRA n18 Qm=0.714 from S. Jose de Safira, Minas Gerais, Brazil
Sample: Annealed at T = 650 C for t = 20 m
Note: Occupancies calculated assuming complete Fe/Mn disorder
_database_code_amcsd 0003853
14.2501 5.7263 5.0767 90 90 90 Pbcn
atom       x      y      z  occ  Uiso
FeA        0 .32898    .25 .640 .0069
NbA        0 .32898    .25 .188 .0069
MnA        0 .32898    .25 .169 .0069
TaA        0 .32898    .25 .003 .0069
NbB  .162739 .17765 .74783 .856 .0057
FeB  .162739 .17765 .74783 .075 .0057
TaB  .162739 .17765 .74783 .049 .0057
MnB  .162739 .17765 .74783 .020 .0057
O1    .09526 .10613  .0714      .0085
O2    .41987 .11665  .0942      .0093
O3    .75626 .12201  .0822      .0078