data_global _chemical_name_mineral 'Chopinite' loop_ _publ_author_name 'Berthet G' 'Joubert J' 'Bertaut E' _journal_name_full 'Zeitschrift fur Kristallographie' _journal_volume 136 _journal_year 1972 _journal_page_first 98 _journal_page_last 105 _publ_section_title ; Vacancies ordering in new metastable orthophosphates (Co3)P2O8 and (Mg3)P2O8 with olivine-related structure _cod_database_code 1008830 ; _database_code_amcsd 0016699 _chemical_formula_sum 'Mg3 P2 O8' _cell_length_a 5.911 _cell_length_b 10.214 _cell_length_c 4.734 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90.99 _cell_volume 285.772 _exptl_crystal_density_diffrn 3.055 _symmetry_space_group_name_H-M 'P 1 1 21/b' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,1/2+y,1/2-z' '-x,1/2-y,1/2+z' '-x,-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z Mg1 0.50000 0.00000 0.00000 Mg2 0.26300 0.27700 -0.02300 P1 0.24200 0.10300 0.42600 O1 0.26600 0.07900 0.74600 O2 0.23900 0.45300 0.20200 O3 0.05900 0.19000 0.35000 O4 0.43900 0.14500 0.27200