CO2 Gibbs G V, Boisen M B, Downs R T, Lasaga A C Materials Research Society Symposia Proceedings 121 (1988) 155-165 Mathematical Modeling of the structures and bulk moduli of TX2 quartz and cristobalite structure types, T = C, Si, Ge and X = O, S Locality: theoretical, cristobalite structure _database_code_amcsd 0018756 4.033 4.033 5.097 90 90 90 P4_12_12 atom x y z C .332 .332 0 O .223 .163 .216