KZn(HP~2~O~7~)·2H~2~O and KMn(HP~2~O~7~)·2H~2~O: acid pyrophosphate metallates(II) with layer structures
Assaaoudi, Hassane; Ennaciri, Abdelaziz; Harcharras, Mohamed; El Bali, Brahim; Reinauer, Felix; Glaum, Robert; Rulmont, André; Spirlet, Marie-Rose; Acta Crystallographica Section C 58 (2002) i79–i81; doi:10.1107/S0108270102007394

data_2012741
_publ_section_title
;
 KZn(HP~2~O~7~)&#x00B7;2H~2~O and KMn(HP~2~O~7~)&#x00B7;2H~2~O: acid
 pyrophosphate metallates(II) with layer structures
;
_journal_issue                   6
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              i79
_journal_page_last               i81
_journal_paper_doi               10.1107/S0108270102007394
_journal_volume                  58
_journal_year                    2002
_chemical_formula_iupac          'K Zn (H P2 O7) (H2 O)2'
_chemical_formula_structural     'K Zn (H P2 O7) (H2 O)2'
_chemical_formula_sum            'H5 K O9 P2 Zn'
_chemical_formula_weight         315.45
_chemical_name_systematic
;
potassium zinc hydrogen pyrophosphate dihydrate
;
_space_group_IT_number           62
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2ac 2n'
_symmetry_space_group_name_H-M   'P n m a'
_atom_sites_solution_hydrogens   difmap
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   15.4727(12)
_cell_length_b                   7.7820(9)
_cell_length_c                   6.5009(7)
_cell_measurement_reflns_used    40
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      17.47
_cell_measurement_theta_min      5.27
_cell_volume                     782.76(14)
_computing_cell_refinement       XSCANS
_computing_data_collection       'XSCANS (Siemens, 1996)'
_computing_data_reduction        'SHELXTL (Siemens, 1991)'
_computing_molecular_graphics    SHELXTL
_computing_publication_material  SHELXTL
_computing_structure_refinement  SHELXTL
_computing_structure_solution    SHELXTL
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 1.0
_diffrn_measured_fraction_theta_max 1.0
_diffrn_measurement_device_type  'Bruker P4'
_diffrn_measurement_method       2\q/\w
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0251
_diffrn_reflns_av_sigmaI/netI    0.0290
_diffrn_reflns_limit_h_max       18
_diffrn_reflns_limit_h_min       -1
_diffrn_reflns_limit_k_max       1
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       7
_diffrn_reflns_limit_l_min       -1
_diffrn_reflns_number            1080
_diffrn_reflns_theta_full        25.0
_diffrn_reflns_theta_max         25.0
_diffrn_reflns_theta_min         2.63
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 97
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    4.101
_exptl_absorpt_correction_T_max  0.986
_exptl_absorpt_correction_T_min  0.589
_exptl_absorpt_correction_type   '\y scan'
_exptl_absorpt_process_details   '(North et al., 1968)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    2.677
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prismatic
_exptl_crystal_F_000             624
_exptl_crystal_size_max          0.4
_exptl_crystal_size_mid          0.4
_exptl_crystal_size_min          0.3
_refine_diff_density_max         0.426
_refine_diff_density_min         -0.383
_refine_ls_extinction_coef       0.0275(18)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXTL
_refine_ls_goodness_of_fit_ref   1.108
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     77
_refine_ls_number_reflns         738
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.108
_refine_ls_R_factor_all          0.0278
_refine_ls_R_factor_gt           0.0252
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w = 1/[\s^2^(Fo^2^)+(0.0335P)^2^+0.9013P] where P = (Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0645
_refine_ls_wR_factor_ref         0.0661
_reflns_number_gt                692
_reflns_number_total             738
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            br1366.cif
_cod_data_source_block           I
_cod_database_code               2012741
_cod_database_fobs_code          2012741