Berzelianite Heyding R D, Murray R M Canadian Journal of Chemistry 54 (1976) 841-848 Crystal structures of Cu1.8Se, Cu3Se2, alpha- and gamma CuSe, CuSe2, and CuSe2II Locality: synthetic _database_code_amcsd 0012163 5.765 5.765 5.765 90 90 90 Fm3m atom x y z occ Biso Cu1 .25 .25 .25 .647 2.5 Cu2 1/3 1/3 1/3 .063 2.5 Se 0 0 0 2