data_global
_chemical_name_mineral 'Archerite'
loop_
_publ_author_name
'Nelmes R J'
'Meyer G M'
'Tibballs J E'
_journal_name_full 'Journal of Physics C: Solid State Physics'
_journal_volume 15 
_journal_year 1982
_journal_page_first 59
_journal_page_last 75
_publ_section_title
;
 The crystal structure of tetragonal KH2PO4
 and KD2PO4 as a function of temperature
 Sample: T = 127 K
;
_database_code_amcsd 0013164
_chemical_formula_sum 'K H2 P O4'
_cell_length_a 7.4264
_cell_length_b 7.4264
_cell_length_c 6.931
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 382.255
_exptl_crystal_density_diffrn      2.365
_symmetry_space_group_name_H-M 'I -4 2 d'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,1/2+z'
  '1/2-y,-x,3/4+z'
  '-y,1/2-x,1/4+z'
  'y,-x,-z'
  '1/2+y,1/2-x,1/2-z'
  '-x,1/2+y,1/4-z'
  '1/2-x,+y,3/4-z'
  '-x,-y,z'
  '1/2-x,1/2-y,1/2+z'
  '1/2+y,x,3/4+z'
  '+y,1/2+x,1/4+z'
  '-y,x,-z'
  '1/2-y,1/2+x,1/2-z'
  'x,1/2-y,1/4-z'
  '1/2+x,-y,3/4-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
K   0.00000   0.00000   0.50000   1.00000
H   0.14867   0.22713   0.12266   0.50000
P   0.00000   0.00000   0.00000   1.00000
O   0.14933   0.08283   0.12675   1.00000
loop_
_atom_site_aniso_label
_atom_site_aniso_U_11
_atom_site_aniso_U_22
_atom_site_aniso_U_33
_atom_site_aniso_U_12
_atom_site_aniso_U_13
_atom_site_aniso_U_23
K 0.00922 0.00922 0.00660 0.00000 0.00000 0.00000
H 0.01720 0.01660 0.01990 -0.00050 -0.00180 -0.00070
P 0.00520 0.00520 0.00810 0.00000 0.00000 0.00000
O 0.00680 0.00700 0.00910 0.00060 -0.00500 -0.00170