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