data_global
_amcsd_formula_title 'Ca2CoSi2O7'
loop_
_publ_author_name
'Kusaka K'
'Hagiya K'
'Ohmasa M'
'Okano Y'
'Mukai M'
'Iishi K'
'Haga N'
_journal_name_full 'Physics and Chemistry of Minerals'
_journal_volume 28 
_journal_year 2001
_journal_page_first 150
_journal_page_last 166
_publ_section_title
;
 Determination of structures of Ca2CoSi2O7, Ca2MgSi2O7, and Ca2(Mg.55Fe.45)Si2O7
 in incommensurate and normal phases and observation of diffuse streaks at high temperature
 Sample: T = 468 K
 Melilite group
;
_database_code_amcsd 0008510
_chemical_formula_sum 'Co Ca2 Si2 O7'
_cell_length_a 7.8563
_cell_length_b 7.8563
_cell_length_c 5.0294
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 310.422
_exptl_crystal_density_diffrn      3.287
_symmetry_space_group_name_H-M 'P -4 21 m'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2-y,1/2-x,z'
  'y,-x,-z'
  '1/2-x,1/2+y,-z'
  '-x,-y,z'
  '1/2+y,1/2+x,z'
  '-y,x,-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
Co   0.00000   0.00000   0.00000   0.01558
Ca   0.33140   0.16860   0.50470   0.02584
Si   0.13910   0.36090   0.93750   0.01381
O1   0.00000   0.50000   0.82100   0.04179
O2   0.14060   0.35940   0.25440   0.02862
O3   0.08050   0.18910   0.78490   0.03673