data_global _chemical_name_mineral 'Lawsonite' loop_ _publ_author_name 'Meyer H W' 'Marion S' 'Sondergeld P' 'Carpenter M A' 'Knight K S' 'Redfern S A T' 'Dove M T' _journal_name_full 'American Mineralogist' _journal_volume 86 _journal_year 2001 _journal_page_first 566 _journal_page_last 577 _publ_section_title ; Displacive components of the low-temperature phase transitions in lawsonite T = 50 K ; _database_code_amcsd 0002633 _chemical_formula_sum 'Ca (Al1.94 Fe.06) Si2 O10 D4' _cell_length_a 5.8639 _cell_length_b 8.76442 _cell_length_c 13.099 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 673.206 _exptl_crystal_density_diffrn 3.157 _symmetry_space_group_name_H-M 'P 21 c n' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,1/2-y,1/2+z' '1/2+x,1/2+y,1/2-z' '1/2+x,-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_occupancy _atom_site_U_iso_or_equiv Ca -0.27200 0.08110 0.25060 1.00000 0.00260 Al 0.00000 0.00000 -0.00400 0.97000 0.00130 Fe 0.00000 0.00000 -0.00400 0.03000 0.00130 Ala -0.00600 -0.00200 0.49700 0.97000 0.00130 Fea -0.00600 -0.00200 0.49700 0.03000 0.00130 Si -0.25300 0.73000 0.13200 1.00000 0.00110 Sia -0.25400 0.72700 0.36600 1.00000 0.00110 O1 -0.24700 -0.20160 0.24850 1.00000 0.00440 O2 0.01700 0.11850 0.12480 1.00000 0.00280 O2a 0.01300 0.12550 0.38190 1.00000 0.00280 O2b 0.46600 0.36640 0.88690 1.00000 0.00280 O2c 0.47800 0.37410 0.61700 1.00000 0.00280 O3 -0.26100 -0.11320 0.06350 1.00000 0.00140 O3a -0.25700 -0.11540 0.43370 1.00000 0.00140 O4 -0.26400 0.39120 0.05120 1.00000 0.00220 O4a -0.25500 0.38060 0.46090 1.00000 0.00220 O5 -0.23900 0.35920 0.24820 1.00000 0.00390 Dw -0.25900 0.38270 0.17260 1.00000 0.02260 Dwa 0.69400 0.44080 0.28430 1.00000 0.03200 Dh -0.25600 0.27920 0.02880 1.00000 0.02170 Dha -0.24300 0.32250 0.40170 1.00000 0.02900