Mg~7~(AsO~4~)~2~(HAsO~4~)~4~: a new magnesium arsenate with a very strong hydrogen bond
Kolitsch, Uwe; Bartu, Petr; Acta Crystallographica Section C 60 (2004) i94–i96; doi:10.1107/S010827010401813X

data_2014290
_publ_section_title
;
 Mg~7~(AsO~4~)~2~(HAsO~4~)~4~: a new magnesium arsenate with a very
 strong hydrogen bond
;
_journal_issue                   9
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              i94
_journal_page_last               i96
_journal_paper_doi               10.1107/S010827010401813X
_journal_volume                  60
_journal_year                    2004
_chemical_formula_iupac          'Mg7 (As O4)2 (H As O4)4'
_chemical_formula_structural     'Mg7 (As O4)2 (As O3 OH)4'
_chemical_formula_sum            'As6 H4 Mg7 O24'
_chemical_formula_weight         1007.72
_chemical_name_common            'magnesium hydrogen arsenate'
_chemical_name_systematic
;
heptamagnesium bis(arsenate) tetrakis(hydrogenarsenate)
;
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   difmap
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_cell_angle_alpha                104.70(3)
_cell_angle_beta                 107.89(3)
_cell_angle_gamma                101.16(3)
_cell_formula_units_Z            1
_cell_length_a                   6.6440(10)
_cell_length_b                   8.042(2)
_cell_length_c                   9.750(2)
_cell_measurement_reflns_used    2620
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      30.034
_cell_measurement_theta_min      2.037
_cell_volume                     458.2(2)
_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
'ATOMS (Dowty, 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 0.995
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device_type  'Nonius KappaCCD area-detector'
_diffrn_measurement_method       '\y and \w'
_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  0.0150
_diffrn_reflns_av_sigmaI/netI    0.0233
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       13
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            5192
_diffrn_reflns_theta_full        29.94
_diffrn_reflns_theta_max         29.94
_diffrn_reflns_theta_min         2.33
_diffrn_standards_decay_%        0
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    11.187
_exptl_absorpt_correction_T_max  0.6632
_exptl_absorpt_correction_T_min  0.3471
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(HKL SCALEPACK; Otwinowski & Minor, 1997)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    3.652
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             478
_exptl_crystal_size_max          0.12
_exptl_crystal_size_mid          0.07
_exptl_crystal_size_min          0.04
_refine_diff_density_max         1.085
_refine_diff_density_min         -0.994
_refine_ls_extinction_coef       0.0034(6)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL97 (Sheldrick, 1997)'
_refine_ls_goodness_of_fit_ref   1.093
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     178
_refine_ls_number_reflns         2649
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.093
_refine_ls_R_factor_all          0.0297
_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^)+(0.025P)^2^+1.44P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0598
_refine_ls_wR_factor_ref         0.0614
_reflns_number_gt                2411
_reflns_number_total             2649
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            ta1465.cif
_cod_data_source_block           I
_cod_depositor_comments
;
The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'not measured' was changed to '?'
- the value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 
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_cod_database_code               2014290
_cod_database_fobs_code          2014290