Witherite Antao S M, Hassan I Physics and Chemistry of Minerals 34 (2007) 573-580 BaCO3: high-temperature crystal structures and the Pmcn --> R3m phase transition at 811 C Locality: synthetic Sample: T = 93 C _database_code_amcsd 0009099 5.3140 8.9146 6.4642 90 90 90 Pmcn atom x y z Uiso Ba .25 .4163 .7563 .0079 C .25 .7447 -.0696 .0311 O1 .25 .9000 -.0760 .0311 O2 .4661 .6814 -.0779 .0311