data_global
_chemical_name_mineral 'Johannsenite'
loop_
_publ_author_name
'Freed R L'
'Peacor D R'
_journal_name_full 'American Mineralogist'
_journal_volume 52
_journal_year 1967
_journal_page_first 709
_journal_page_last 720
_publ_section_title
;
 Refinement of the crystal structure of johannsenite
;
_database_code_amcsd 156
_chemical_formula_sum 'Ca Mn Si2 O6'
_cell_length_a 9.978
_cell_length_b 9.156
_cell_length_c 5.293
_cell_angle_alpha 90.0
_cell_angle_beta 105.48
_cell_angle_gamma 90.0
_cell_volume 466.019
_exptl_crystal_density_diffrn  3.523
_symmetry_space_group_name_H-M 'C 1 2/c 1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,z'
  'x,-y,1/2+z'
  '1/2+x,1/2-y,1/2+z'
  '-x,y,1/2-z'
  '1/2-x,1/2+y,1/2-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_U_iso_or_equiv
Ca   0.0  0.6981  0.75  0.00735
Mn   0.0  0.0947  0.75  0.00608
Si   0.2129  0.4083  0.7637  0.00329
O1   0.3797  0.407  0.8459  0.00494
O2   0.1368  0.2569  0.6705  0.00595
O3   0.1518  0.4794  0.0043  0.00507