Actinium
Wyckoff R W G
Crystal Structures 1 (1963) 7-83
Second edition. Interscience Publishers, New York, New York
Cubic closest packed, ccp, structure
_database_code_amcsd 0011134
5.311 5.311 5.311 90 90 90 Fm3m
atom  x  y  z
Ac    0  0  0