Alkali scandium arsenates. I. The framework structures of KSc(HAsO~4~)~2~ and RbScAs~2~O~7~
Schwendtner, Karolina; Kolitsch, Uwe; Acta Crystallographica Section C 60 (2004) i79–i83; doi:10.1107/S0108270104015938

data_2014101
_publ_section_title
;
 Alkali scandium arsenates. I. The framework structures of
 KSc(HAsO~4~)~2~ and RbScAs~2~O~7~
;
_journal_issue                   9
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              i79
_journal_page_last               i83
_journal_paper_doi               10.1107/S0108270104015938
_journal_volume                  60
_journal_year                    2004
_chemical_formula_iupac          'Rb1 Sc1 (As2 O7)'
_chemical_formula_structural     'Rb1 Sc1 (As2 O7)'
_chemical_formula_sum            'As2 O7 Rb Sc'
_chemical_formula_weight         392.27
_chemical_name_common            'rubidium scandium diarsenate'
_chemical_name_systematic        ' rubidium scandium diarsenate(V)'
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   none
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_cell_angle_alpha                90.00
_cell_angle_beta                 106.45(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   7.837(2)
_cell_length_b                   10.625(2)
_cell_length_c                   8.778(2)
_cell_measurement_reflns_used    2668
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      32.577
_cell_measurement_theta_min      2.037
_cell_volume                     701.0(3)
_computing_cell_refinement       'HKL SCALEPACK (Otwinowski & Minor 1997)'
_computing_data_collection       'COLLECT (Nonius, 2003)'
_computing_data_reduction
'HKL DENZO (Otwinowski & Minor, 1997) and SCALEPACK'
_computing_molecular_graphics
'Diamond (Pennington, 1999) and ORTEP-3 for Windows (Farrugia, 1997)'
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Nonius KappaCCD'
_diffrn_measurement_method       '\y and \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0185
_diffrn_reflns_av_sigmaI/netI    0.0262
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       13
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            4967
_diffrn_reflns_theta_full        32.58
_diffrn_reflns_theta_max         32.58
_diffrn_reflns_theta_min         2.71
_diffrn_standards_decay_%        0
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    17.305
_exptl_absorpt_correction_T_max  0.4783
_exptl_absorpt_correction_T_min  0.3382
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(HKL SCALEPACK; Otwinowski & Minor, 1997)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    3.717
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       'irregular fragment'
_exptl_crystal_F_000             720
_exptl_crystal_size_max          0.08
_exptl_crystal_size_mid          0.07
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.834
_refine_diff_density_min         -1.065
_refine_ls_extinction_coef       0.0018(3)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL97
_refine_ls_goodness_of_fit_ref   1.049
_refine_ls_hydrogen_treatment    none
_refine_ls_matrix_type           full
_refine_ls_number_parameters     101
_refine_ls_number_reflns         2544
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.049
_refine_ls_R_factor_all          0.0326
_refine_ls_R_factor_gt           0.0232
_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^)+(0.025P)^2^+0.77P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0515
_refine_ls_wR_factor_ref         0.0540
_reflns_number_gt                2152
_reflns_number_total             2544
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            bc1052.cif
_cod_data_source_block           II
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_original_formula_sum        'As2 O7 Rb1 Sc1'
_cod_database_code               2014101
_cod_database_fobs_code          2014101