data_global
_chemical_name_mineral 'Brandtite'
loop_
_publ_author_name
'Dahlman B'
_journal_name_full 'Arkiv for Mineralogi och Geologi'
_journal_volume 1 
_journal_year 1952
_journal_page_first 339
_journal_page_last 366
_publ_section_title
;
 The crystal structures of krohnkite, CuNa2(SO4)2*2H2O and brandtite, MnCa2(AsO4)2*2H2O
;
_database_code_amcsd 0012042
_chemical_compound_source 'Harstigen mine, Sweden'
_chemical_formula_sum 'Mn Ca2 As2 O10 H4'
_cell_length_a 5.65
_cell_length_b 12.80
_cell_length_c 5.65
_cell_angle_alpha 90
_cell_angle_beta 80.5
_cell_angle_gamma 90
_cell_volume 403.004
_exptl_crystal_density_diffrn      3.700
_symmetry_space_group_name_H-M 'P 1 21/c 1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  'x,1/2-y,1/2+z'
  '-x,1/2+y,1/2-z'
  '-x,-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
Mn   0.00000   0.00000   0.00000
Ca   0.42800   0.12000   0.25300
As   0.77700   0.12200   0.56600
O1   0.04800   0.16500   0.52200
O2   0.69400   0.05500   0.81600
O3   0.75600   0.03000   0.33600
O4   0.55900   0.20800   0.56600
Wat   0.20800   0.13600   0.93500