data_global
_chemical_name_mineral 'Helium'
loop_
_publ_author_name
'Schuch A F'
'Mills R L'
_journal_name_full 'Physical Review Letters'
_journal_volume 8 
_journal_year 1962
_journal_page_first 469
_journal_page_last 470
_publ_section_title
;
 Structure of the gamma form of solid He4
 Sample: at T = 1.73 K & P = .003 GPa
;
_database_code_amcsd 0015274
_chemical_compound_source 'Synthetic'
_chemical_formula_sum 'He'
_cell_length_a 3.650
_cell_length_b 3.650
_cell_length_c 5.945
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 120
_cell_volume 68.591
_exptl_crystal_density_diffrn      0.194
_symmetry_space_group_name_H-M 'P 63/m m c'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '-x,-x+y,1/2+z'
  'x,x-y,1/2-z'
  '-x+y,-x,1/2-z'
  'x-y,x,1/2+z'
  '-y,-x,z'
  'y,x,-z'
  'y,-x+y,-z'
  '-y,x-y,z'
  'x-y,-y,1/2+z'
  '-x+y,y,1/2-z'
  'x,y,1/2-z'
  '-x,-y,1/2+z'
  'x,x-y,z'
  '-x,-x+y,-z'
  'x-y,x,-z'
  '-x+y,-x,z'
  'y,x,1/2+z'
  '-y,-x,1/2-z'
  '-y,x-y,1/2-z'
  'y,-x+y,1/2+z'
  '-x+y,y,z'
  'x-y,-y,-z'
  '-x,-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
He   0.33333   0.66667   0.25000