data_global _chemical_name_mineral 'Reedmergnerite' loop_ _publ_author_name 'Downs R T' 'Yang H' 'Hazen R M' 'Finger L W' 'Prewitt C T' _journal_name_full 'American Mineralogist' _journal_volume 84 _journal_year 1999 _journal_page_first 333 _journal_page_last 340 _publ_section_title ; Compressibility mechanisms of alkali feldspars: New data from reedmergnerite Sample from Joseph Smith #1 mine, Duchesne Co., Utah, NMNH 140 P = 3.64 GPa ; _database_code_amcsd 0002219 _chemical_formula_sum 'Na B Si3 O8' _cell_length_a 7.6194 _cell_length_b 12.2465 _cell_length_c 6.7389 _cell_angle_alpha 93.392 _cell_angle_beta 116.222 _cell_angle_gamma 92.263 _cell_volume 561.599 _exptl_crystal_density_diffrn 2.910 _symmetry_space_group_name_H-M 'C -1' loop_ _space_group_symop_operation_xyz 'x,y,z' '1/2+x,1/2+y,z' '-x,-y,-z' '1/2-x,1/2-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv Na 0.25413 0.00896 0.12996 ? B 0.01183 0.15812 0.22019 0.00709 Si1m 0.00459 0.81009 0.20710 0.00773 Si2o 0.69921 0.09857 0.32068 0.00773 Si2m 0.67376 0.86175 0.35290 0.00773 O(A1) 0.00533 0.13397 0.99985 0.01051 O(A2) 0.57848 0.97881 0.27190 0.00899 O(B)o 0.84859 0.08772 0.21711 0.01102 O(B)m 0.81109 0.83342 0.23341 0.01165 O(C)o -0.00747 0.27224 0.27229 0.00887 O(C)m 0.02686 0.67878 0.19875 0.01229 O(D)o 0.20023 0.12160 0.38361 0.01330 O(D)m 0.19499 0.86901 0.41481 0.01381 loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_12 _atom_site_aniso_U_13 _atom_site_aniso_U_23 Na 0.01587 0.02244 0.02932 0.00366 0.01069 -0.00495