Freboldite
Wyckoff R W G
Crystal Structures 1 (1963) 85-237
Second edition. Interscience Publishers, New York, New York
Note: ideal nickel arsenide structure
_database_code_amcsd 0011564
3.6294 3.6294 5.3006 90 90 120 P6_3mc
atom   x   y   z
Co     0   0   0
Se   1/3 2/3 .25