data_global
_chemical_name_mineral 'Orthoclase'
loop_
_publ_author_name
'Fenn P M'
'Brown G E'
_journal_name_full 'Zeitschrift fur Kristallographie'
_journal_volume 145 
_journal_year 1977
_journal_page_first 124
_journal_page_last 145
_publ_section_title
;
 Crystal structure of a synthetic, compositionally intermediate,
 hypersolvus alkali feldspar: evidence for Na, K site ordering
;
_database_code_amcsd 0020553
_chemical_compound_source 'Synthetic'
_chemical_formula_sum 'K.58 Na.42 (Si2.99 Al1.01) O8'
_cell_length_a 8.434
_cell_length_b 13.015
_cell_length_c 7.1717
_cell_angle_alpha 90
_cell_angle_beta 116.09
_cell_angle_gamma 90
_cell_volume 707.012
_exptl_crystal_density_diffrn      2.551
_symmetry_space_group_name_H-M 'C 1 -1 1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,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_occupancy
_atom_site_U_iso_or_equiv
K1   0.27870   0.00000   0.13570   0.50000   0.02267
K2   0.28800  -0.00120   0.14160   0.08000   0.11905
Na1   0.28800  -0.00120   0.14160   0.42000   0.11905
Si1   0.00860   0.18160   0.22370   0.71000   0.01621
Al1   0.00860   0.18160   0.22370   0.29000   0.01621
Si2   0.00830   0.81830   0.22350   0.72000   0.01596
Al2   0.00830   0.81830   0.22350   0.28000   0.01596
Si3   0.70190   0.11700   0.34300   0.78000   0.01558
Al3   0.70190   0.11700   0.34300   0.22000   0.01558
Si4   0.70200   0.88280   0.34300   0.78000   0.01545
Al4   0.70200   0.88280   0.34300   0.22000   0.01545
O1   0.00000   0.14260  -0.00020   1.00000   0.02533
O2   0.61840   0.00020   0.28420   1.00000   0.02495
O3   0.82620   0.14110   0.22680   1.00000   0.02609
O4   0.82660   0.85880   0.22750   1.00000   0.02520
O5   0.02910   0.30810   0.25540   1.00000   0.02254
O6   0.02890   0.69220   0.25590   1.00000   0.02280
O7   0.18470   0.12610   0.40420   1.00000   0.02343
O8   0.18450   0.87430   0.40410   1.00000   0.02356