data_global _chemical_name_mineral 'Ramsdellite' loop_ _publ_author_name 'Post J E' 'Heaney P J' _journal_name_full 'American Mineralogist' _journal_volume 89 _journal_year 2004 _journal_page_first 969 _journal_page_last 975 _publ_section_title ; Neutron and synchrotron X-ray diffraction study of the structures and dehydration behaviors of ramsdellite and "groutellite" ; _database_code_amcsd 0003565 _chemical_formula_sum 'Mn O2' _cell_length_a 9.2734 _cell_length_b 2.8638 _cell_length_c 4.5219 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 120.089 _exptl_crystal_density_diffrn 4.809 _symmetry_space_group_name_H-M 'P n m a' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,1/2-y,z' '-x,1/2+y,-z' '1/2-x,1/2+y,1/2+z' '1/2+x,1/2-y,1/2-z' '1/2+x,y,1/2-z' '1/2-x,-y,1/2+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 Mn 0.13320 0.25000 0.02580 0.00210 O1 0.96550 0.25000 0.78380 0.00410 O2 0.27960 0.25000 0.32010 0.00340