data_global _chemical_name_mineral 'Epididymite' loop_ _publ_author_name 'Gatta G D' 'Rotiroti N' 'McIntyre G J' 'Guastoni A' 'Nestola F' _journal_name_full 'American Mineralogist' _journal_volume 93 _journal_year 2008 _journal_page_first 1158 _journal_page_last 1165 _publ_section_title ; New insights into the crystal chemistry of epididymite and eudidymite from Malosa, Malawi: A single-crystal neutron diffraction study ; _database_code_amcsd 0004614 _chemical_compound_source 'Malosa, Malawi' _chemical_formula_sum 'Na Be Si3 O8 H' _cell_length_a 12.7334 _cell_length_b 13.6298 _cell_length_c 7.3467 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 1275.047 _exptl_crystal_density_diffrn 2.555 _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 Na 0.10285 0.06934 0.50192 0.02660 Be 0.49472 -0.00042 0.34273 0.00670 Si1 0.15908 0.13780 0.01543 0.00510 Si2 0.34260 0.13635 0.73115 0.00540 Si3 0.33173 0.13741 0.30525 0.00590 O1 0.12005 0.25000 0.00001 0.01390 O2 0.21704 0.12240 0.21004 0.01180 O3 0.06068 0.06612 0.00658 0.00720 O4 0.23777 0.11405 0.84938 0.01480 O5 0.43489 0.06457 0.78946 0.00900 O6 0.37761 0.25000 0.76529 0.01200 O7 0.30497 0.12340 0.52074 0.01060 O8 0.37000 0.25000 0.26883 0.01150 O9 0.41552 0.06300 0.22624 0.00950 OW 0.05713 0.25000 0.48974 0.02880 H1 0.00647 0.25000 0.58561 0.05150 H2 0.01340 0.25000 0.38486 0.05860 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 0.03770 0.02200 0.02010 -0.00740 0.00530 -0.00150 Be 0.00680 0.00680 0.00650 0.00050 0.00020 0.00010 Si1 0.00400 0.00490 0.00620 -0.00080 0.00010 -0.00020 Si2 0.00510 0.00540 0.00590 0.00060 0.00120 -0.00070 Si3 0.00650 0.00550 0.00580 0.00100 -0.00170 -0.00020 O1 0.01360 0.00390 0.02410 0.00000 -0.00310 0.00000 O2 0.00840 0.01620 0.01090 -0.00140 -0.00490 0.00050 O3 0.00680 0.00770 0.00710 -0.00340 -0.00020 -0.00030 O4 0.01080 0.01860 0.01510 -0.00260 0.00780 -0.00210 O5 0.01000 0.00930 0.00760 0.00420 0.00040 -0.00060 O6 0.01330 0.00540 0.01730 0.00000 -0.00320 0.00000 O7 0.01200 0.01310 0.00680 0.00190 -0.00090 -0.00020 O8 0.01240 0.00560 0.01640 0.00000 0.00220 0.00000 O9 0.01130 0.00940 0.00770 0.00450 -0.00130 -0.00060 OW 0.02150 0.03160 0.03330 0.00000 0.00600 0.00000 H1 0.04400 0.05100 0.05900 0.00000 0.02400 0.00000 H2 0.06000 0.06000 0.05500 0.00000 -0.01500 0.00000