data_global _chemical_name_mineral 'Lawsonite' loop_ _publ_author_name 'Libowitzky E' 'Armbruster T' _journal_name_full 'American Mineralogist' _journal_volume 80 _journal_year 1995 _journal_page_first 1277 _journal_page_last 1285 _publ_section_title ; Low-temperature phase transitions and the role of hydrogen bonds in lawsonite Sample: T = 110 K ; _database_code_amcsd 0001763 _chemical_formula_sum 'Ca Al2 Si2 O10 H4' _cell_length_a 5.855 _cell_length_b 8.762 _cell_length_c 13.094 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 671.742 _exptl_crystal_density_diffrn 3.107 _symmetry_space_group_name_H-M 'P 21 c n' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,-y,1/2+z' '1/2+x,1/2+y,1/2-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 Ca 0.00660 0.33176 0.25106 0.00394 Al 0.25000 0.24952 -0.00036 0.00243 Ala 0.24580 0.25214 0.50131 0.00205 Si -0.00310 0.98003 0.13181 0.00251 Sia -0.00100 0.97795 0.36558 0.00260 O1 -0.00760 0.04990 0.24891 0.00443 O2 0.27520 0.37310 0.11920 0.00465 O2a 0.26750 0.38180 0.38584 0.00465 O2b 0.72370 0.62350 0.88203 0.00465 O2c 0.72390 0.62810 0.62160 0.00465 O3 0.00240 0.13682 0.06297 0.00367 O3a -0.00110 0.13475 0.43428 0.00405 O4a -0.00070 0.63200 0.45967 0.00393 O4 -0.00620 0.63950 0.05075 0.00481 O5 -0.01300 0.60940 0.24811 0.00836 Hw -0.00400 0.64000 0.18300 0.03546 Hwa 0.95800 0.68900 0.28300 0.04306 Hh 0.00800 0.53900 0.03700 0.03166 Hha 0.04300 0.57600 0.41400 0.06839