Crystal chemistry of transition metal diarsenates <i>M</i>~2~As~2~O~7~ (<i>M</i> = Mn, Co, Ni, Zn): variants of the thortveitite structure
Weil, Matthias; Stöger, Berthold; Acta Crystallographica Section B 66 (2010) 603–614; doi:10.1107/S0108768110040802

data_2104861
_publ_section_title
;
 Crystal chemistry of transition metal diarsenates <i>M</i>~2~As~2~O~7~
 (<i>M</i> = Mn, Co, Ni, Zn): variants of the thortveitite structure
;
_journal_coeditor_code           SN5100
_journal_issue                   6
_journal_name_full               'Acta Crystallographica Section B'
_journal_page_first              603
_journal_page_last               614
_journal_paper_doi               10.1107/S0108768110040802
_journal_volume                  66
_journal_year                    2010
_chemical_formula_structural     'Zn2 As2 O7'
_chemical_formula_sum            'As2 O7 Zn2'
_chemical_formula_weight         392.6
_chemical_name_systematic
;
Zinc(II) diarsenate(V)
;
_space_group_ssg_name            C2/m(\a0\g)0s
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_cell_angle_beta                 105.3190(10)
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   6.72480(10)
_cell_length_b                   8.4605(2)
_cell_length_c                   4.77910(10)
_cell_modulation_dimension       1
_cell_volume                     262.247(9)
_computing_cell_refinement       APEX2
_computing_data_collection       'APEX2 (Bruker, 2004)'
_computing_data_reduction        APEX2
_computing_publication_material
'Jana2006 (Petricek, Dusek & Palatinus, 2006)'
_computing_structure_refinement
'Jana2006 (Petricek, Dusek & Palatinus, 2006)'
_computing_structure_solution    'coordinates taken from an isotypic compound'
_diffrn_ambient_temperature      293
_diffrn_measured_fraction_theta_full 0.98
_diffrn_measured_fraction_theta_max 0.96
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'Bruker APEXII CCD'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'X-ray tube'
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71069
_diffrn_reflns_av_R_equivalents  0.042
_diffrn_reflns_av_sigmaI/netI    0.0435
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_index_m_1_max 2
_diffrn_reflns_limit_index_m_1_min -2
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       -18
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -11
_diffrn_reflns_number            24775
_diffrn_reflns_theta_full        55.53
_diffrn_reflns_theta_max         56.1
_diffrn_reflns_theta_min         2.02
_exptl_absorpt_coefficient_mu    21.652
_exptl_absorpt_correction_T_max  0.7898
_exptl_absorpt_correction_T_min  0.2120
_exptl_absorpt_correction_type   none
_exptl_absorpt_process_details   'SADABS (Bruker, 2008)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    4.9708
_exptl_crystal_description       fragment
_exptl_crystal_F_000             364
_exptl_crystal_size_max          0.12
_exptl_crystal_size_mid          0.10
_exptl_crystal_size_min          0.05
_refine_diff_density_max         1.22
_refine_diff_density_min         -1.28
_refine_ls_extinction_coef       88E1(4)
_refine_ls_extinction_method
'B-C type 1 Lorentzian isotropic (Becker & Coppens, 1974)'
_refine_ls_goodness_of_fit_ref   0.92
_refine_ls_number_constraints    1
_refine_ls_number_parameters     135
_refine_ls_number_reflns         8539
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.0922
_refine_ls_R_factor_gt           0.0292
_refine_ls_shift/su_max          0.0307
_refine_ls_shift/su_mean         0.0022
_refine_ls_structure_factor_coef F
_refine_ls_weighting_details     w=1/(\s^2^(F)+0.0004F^2^)
_refine_ls_weighting_scheme      sigma
_refine_ls_wR_factor_gt          0.0381
_refine_ls_wR_factor_ref         0.0462
_reflns_number_gt                3694
_reflns_number_total             8539
_reflns_threshold_expression     I>3\s(I)
_cod_data_source_file            sn5100.cif
_cod_data_source_block           beta-Zn2As2O7-superspace
_cod_original_cell_volume        262.216(3)
_cod_database_code               2104861
_cod_database_fobs_code          2104861