data_global _chemical_name_mineral 'Monticellite' loop_ _publ_author_name 'Sharp Z D' 'Hazen R M' 'Finger L W' _journal_name_full 'American Mineralogist' _journal_volume 72 _journal_year 1987 _journal_page_first 748 _journal_page_last 755 _publ_section_title ; High-pressure crystal chemistry of monticellite, CaMgSiO4 Sample: P = 20.7 kbar ; _database_code_amcsd 0001099 _chemical_formula_sum 'Mg Ca Si O4' _cell_length_a 4.800 _cell_length_b 11.004 _cell_length_c 6.346 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 335.191 _exptl_crystal_density_diffrn 3.101 _symmetry_space_group_name_H-M 'P b n m' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,y,1/2-z' '-x,-y,1/2+z' '1/2+x,1/2-y,1/2+z' '1/2-x,1/2+y,1/2-z' '1/2-x,1/2+y,z' '1/2+x,1/2-y,-z' '-x,-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv Mg1 0.00000 0.00000 0.00000 0.01178 Ca2 0.97480 0.27660 0.25000 0.01267 Si 0.41160 0.08010 0.25000 0.01089 O1 0.74120 0.07730 0.25000 0.01545 O2 0.24640 0.44770 0.25000 0.01456 O3 0.27220 0.14820 0.04470 0.01444