MgKSb Pearson W B Zeitschrift fur Kristallographie 171 (1985) 23-39 The Cu2Sb and related structures _database_code_amcsd 0010885 4.812 4.812 8.202 90 90 90 P4/nmm atom x y z Mg 0 0 0 K .5 0 .6456 Sb .5 0 .2001