data_global _chemical_name_mineral 'Nacrite' loop_ _publ_author_name 'Zheng H' 'Bailey S W' _journal_name_full 'Clays and Clay Minerals' _journal_volume 42 _journal_year 1994 _journal_page_first 46 _journal_page_last 52 _publ_section_title ; Refinement of the nacrite structure ; _database_code_amcsd 0012238 _chemical_compound_source 'Red Mountain near Silverton, Colorado, USA' _chemical_formula_sum 'Al2 Si2 O9 H4' _cell_length_a 8.906 _cell_length_b 5.146 _cell_length_c 15.664 _cell_angle_alpha 90 _cell_angle_beta 113.58 _cell_angle_gamma 90 _cell_volume 657.944 _exptl_crystal_density_diffrn 2.606 _symmetry_space_group_name_H-M 'C 1 c 1' loop_ _space_group_symop_operation_xyz 'x,y,z' '1/2+x,1/2+y,z' 'x,-y,1/2+z' '1/2+x,1/2-y,1/2+z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z Al1 0.15520 0.31980 0.21770 Al2 0.49010 0.32450 0.21730 Sil 0.20120 0.47000 0.02770 Si2 0.37150 0.98310 0.02700 O1 0.24110 0.74990 -0.00410 O2 0.27230 0.24700 -0.01880 O3 0.00290 0.44170 -0.01930 O4 0.26960 0.43850 0.13850 O5 0.46180 0.01100 0.13810 O-h1 0.07950 0.01180 0.14320 O-h2 0.55800 0.63420 0.28380 O-h3 0.17800 0.62960 0.28250 O-h4 0.36930 0.20660 0.28260 H1 0.63460 0.45100 0.12770 H2 0.54750 0.67360 0.32790 H3 0.24320 0.60960 0.32960 H4 0.43170 0.13860 0.32280 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 Al1 0.01148 0.01207 0.01775 0.00000 0.00712 -0.00075 Al2 0.01114 0.01100 0.02193 -0.00064 0.00950 -0.00075 Sil 0.01148 0.00698 0.02193 -0.00021 0.00950 0.00000 Si2 0.01215 0.00872 0.01775 -0.00043 0.00772 -0.00037 O1 0.01586 0.01301 0.02401 0.00596 0.00831 0.00187 O2 0.01789 0.01073 0.02401 -0.00277 0.01128 0.00000 O3 0.01148 0.01664 0.01984 -0.00085 0.00712 0.00112 O4 0.00709 0.00631 0.02506 -0.00085 0.00831 -0.00037 O5 0.01350 0.01543 0.02088 -0.00553 0.00831 0.00150 O-h1 0.01789 0.01274 0.02401 0.00511 0.01247 0.00225 O-h2 0.01823 0.01583 0.02088 -0.00340 0.01069 0.00000 O-h3 0.01451 0.01328 0.01984 0.00149 0.00712 0.00000 O-h4 0.01654 0.02066 0.01671 -0.00213 0.00772 -0.00374