data_global
_chemical_name_mineral 'Talmessite'
loop_
_publ_author_name
'Catti M'
'Ferraris G'
'Ivaldi G'
_journal_name_full 'Bulletin de Mineralogie'
_journal_volume 100 
_journal_year 1977
_journal_page_first 230
_journal_page_last 236
_publ_section_title
;
 Hydrogen bonding in the crystalline state. Structure of talmessite,
 Ca2(Mg,Co)(AsO4)2*2H2O, and crystal chemistry of related minerals
;
_database_code_amcsd 0012065
_chemical_compound_source 'Bou-Azzer, Morocco'
_chemical_formula_sum 'Ca2 (Mg.65 Co.35) As2 O10 H4'
_cell_length_a 5.874
_cell_length_b 6.943
_cell_length_c 5.537
_cell_angle_alpha 97.3
_cell_angle_beta 108.7
_cell_angle_gamma 108.1
_cell_volume 196.762
_exptl_crystal_density_diffrn      3.633
_symmetry_space_group_name_H-M 'P -1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '-x,-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
Ca   0.29490   0.76220   0.65290   1.00000
Mg   0.00000   0.00000   0.00000   0.65000
Co   0.00000   0.00000   0.00000   0.35000
As   0.33410   0.24600   0.67030   1.00000
O1   0.34200   0.12720   0.92170   1.00000
O2   0.23850   0.05040   0.39860   1.00000
O3   0.15500   0.39160   0.64120   1.00000
O4   0.63950   0.38640   0.71490   1.00000
Wat   0.95330   0.27780   0.07450   1.00000
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
Ca 0.00950 0.01608 0.00975 0.00722 0.00545 -0.00165
Mg 0.01380 0.02229 0.01672 0.00912 0.00469 -0.00279
Co 0.01380 0.02229 0.01672 0.00912 0.00469 -0.00279
As 0.00266 0.00823 0.00393 0.00165 0.00127 -0.00241
O1 0.01292 0.01799 0.01380 0.00747 0.00709 0.00418
O2 0.01127 0.01874 0.00925 0.00887 -0.00127 -0.00811
O3 0.01343 0.01140 0.01811 0.00798 0.00621 0.00127
O4 0.01140 0.01786 0.01925 0.00203 0.00950 -0.00367
Wat 0.00886 0.01368 0.00507 0.00570 0.00393 -0.00025