data_global _chemical_name_mineral 'Fredrikssonite' loop_ _publ_author_name 'Burns P C' 'Cooper M A' 'Hawthorne F C' _journal_name_full 'The Canadian Mineralogist' _journal_volume 32 _journal_year 1994 _journal_page_first 397 _journal_page_last 403 _publ_section_title ; Jahn-Teller-distorted MnO6 octahedra in fredrikssonite, the fourth polymorph of Mg2Mn(BO3)O2 ; _database_code_amcsd 0005368 _chemical_formula_sum 'Mg3.92 Fe.48 Mn1.56 Al.04 B2 O10' _cell_length_a 9.198 _cell_length_b 12.528 _cell_length_c 2.965 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 341.664 _exptl_crystal_density_diffrn 3.796 _symmetry_space_group_name_H-M 'P b a m' loop_ _space_group_symop_operation_xyz 'x,y,z' '1/2+x,1/2-y,z' '1/2-x,1/2+y,-z' '1/2-x,1/2+y,z' '1/2+x,1/2-y,-z' 'x,y,-z' '-x,-y,z' '-x,-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_occupancy Mg1 0.00000 0.00000 0.00000 1.00000 Mg2 0.50000 0.00000 0.50000 0.92000 Fe2 0.50000 0.00000 0.50000 0.08000 Mg3 0.00480 0.28000 0.00000 1.00000 Mn4 0.74115 0.38458 0.50000 0.78000 Fe4 0.74115 0.38458 0.50000 0.20000 Al4 0.74115 0.38458 0.50000 0.02000 B 0.27820 0.35980 0.50000 1.00000 O1 0.85360 0.04490 0.50000 1.00000 O2 0.38070 0.07860 0.00000 1.00000 O3 0.62770 0.14230 0.50000 1.00000 O4 0.11300 0.14220 0.00000 1.00000 O5 0.85590 0.23490 0.50000 1.00000 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 Mg1 0.00570 0.00580 0.00690 -0.00070 0.00000 0.00000 Mg2 0.00710 0.00540 0.00750 0.00140 0.00000 0.00000 Fe2 0.00710 0.00540 0.00750 0.00140 0.00000 0.00000 Mg3 0.00620 0.00540 0.00670 0.00090 0.00000 0.00000 Mn4 0.00440 0.00530 0.00540 -0.00010 0.00000 0.00000 Fe4 0.00440 0.00530 0.00540 -0.00010 0.00000 0.00000 Al4 0.00440 0.00530 0.00540 -0.00010 0.00000 0.00000 B 0.00880 0.00730 0.00270 -0.00060 0.00000 0.00000 O1 0.00650 0.00760 0.00800 0.00150 0.00000 0.00000 O2 0.00690 0.00520 0.00830 -0.00060 0.00000 0.00000 O3 0.00580 0.00610 0.00930 0.00010 0.00000 0.00000 O4 0.00640 0.00700 0.00820 0.00030 0.00000 0.00000 O5 0.00650 0.00700 0.00870 -0.00160 0.00000 0.00000