data_global _chemical_name_mineral 'Montebrasite' loop_ _publ_author_name 'Groat L A' 'Chakoumakos B C' 'Brouwer D H' 'Hoffman C M' 'Fyfe C A' 'Morell H' 'Schultz A J' _journal_name_full 'American Mineralogist' _journal_volume 88 _journal_year 2003 _journal_page_first 195 _journal_page_last 210 _publ_section_title ; The amblygonite (LiAlPO4F) - montebrasite (LiAlPO4OH) solid solution: A combined powder and single-crystal neutron diffraction and solid-state Li MAS, CP MAS, and REDOR NMR study Sample: from Dunton Gem Min, Oxford County, Maine at T = 75 K ; _database_code_amcsd 0002957 _chemical_formula_sum 'P Al O4.95 F.05 H.95 Li' _cell_length_a 6.7129 _cell_length_b 7.7095 _cell_length_c 7.0231 _cell_angle_alpha 91.359 _cell_angle_beta 117.960 _cell_angle_gamma 91.781 _cell_volume 320.585 _exptl_crystal_density_diffrn 3.025 _symmetry_space_group_name_H-M 'C -1' loop_ _space_group_symop_operation_xyz 'x,y,z' '1/2+x,1/2+y,z' '-x,-y,-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_occupancy _atom_site_U_iso_or_equiv P 0.98340 0.34200 0.26750 1.00000 0.00310 Al1 0.00000 0.00000 0.00000 1.00000 0.00330 Al2 0.00000 0.00000 0.50000 1.00000 0.00290 O1 -0.31800 0.01470 -0.16100 1.00000 0.00450 O2 0.29790 0.05890 0.57270 1.00000 0.00470 O3 0.10240 -0.22370 -0.39000 1.00000 0.00420 O4 0.02560 0.23580 0.10400 1.00000 0.00490 O 0.04900 0.08960 -0.22540 0.95000 0.00440 F 0.04900 0.08960 -0.22540 0.05000 0.00440 H 0.20630 0.13360 0.84800 0.95000 0.01700 Li1 0.06100 -0.32200 0.30900 0.45000 ? Li2 0.08300 -0.32100 0.32200 0.55000 0.01800