Crystal structures of sodium magnesium selenate decahydrate, Na~2~Mg(SeO~4~)~2~·10H~2~O, a new selenate salt, and sodium magnesium selenate dihydrate, Na~2~Mg(SeO~4~)~2~·2H~2~O
Kamburov, Stoyan; Schmidt, Horst; Voigt, Wolfgang; Balarew, Christo; Acta Crystallographica Section C 73 (2017) 582–587; doi:10.1107/S2053229617009330

data_2020805
_publ_section_title
;
 Crystal structures of sodium magnesium selenate decahydrate,
 Na~2~Mg(SeO~4~)~2~&#x00B7;10H~2~O, a new selenate salt, and sodium
 magnesium selenate dihydrate, Na~2~Mg(SeO~4~)~2~&#x00B7;2H~2~O
;
_journal_coeditor_code           KU3198
_journal_issue                   7
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              582
_journal_page_last               587
_journal_paper_doi               10.1107/S2053229617009330
_journal_volume                  73
_journal_year                    2017
_chemical_formula_iupac          'Na2 Mg (Se O4)2, 2H2 O'
_chemical_formula_moiety         'Mg Na2 O8 Se2, 2(H2 O)'
_chemical_formula_sum            'H4 Mg Na2 O10 Se2'
_chemical_formula_weight         392.24
_chemical_name_systematic        'Disodium  magnesium bis(selenate) dihydrate'
_space_group_crystal_system      triclinic
_space_group_IT_number           2
_space_group_name_Hall           '-P 1'
_space_group_name_H-M_alt        'P -1'
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   difmap
_audit_creation_method           SHELXL-2014/7
_cell_angle_alpha                108.36(6)
_cell_angle_beta                 99.07(5)
_cell_angle_gamma                106.63(6)
_cell_formula_units_Z            1
_cell_length_a                   5.556(4)
_cell_length_b                   5.923(4)
_cell_length_c                   7.224(5)
_cell_measurement_reflns_used    3582
_cell_measurement_temperature    200(2)
_cell_measurement_theta_max      29.58
_cell_measurement_theta_min      2.97
_cell_volume                     208.0(3)
_computing_cell_refinement
;
X-AREA (Stoe & Cie, 2002)
;
_computing_data_collection
;
X-AREA (Stoe & Cie, 2002)
;
_computing_data_reduction
;
X-RED (Stoe & Cie, 2002)
;
_computing_molecular_graphics
;
DIAMOND (Brandenburg, 2012)
;
_computing_publication_material
;
publCIF (Westrip, 2010)
;
_computing_structure_refinement
;
SHELXL2014 (Sheldrick, 2015)
;
_computing_structure_solution
;
SHELXS2014 (Sheldrick, 2008)
;
_diffrn_ambient_temperature      200
_diffrn_detector_area_resol_mean 6.67
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.994
_diffrn_measurement_device       '2-circle goniometer'
_diffrn_measurement_device_type  'Stoe IPDS 2T'
_diffrn_measurement_method       'rotation method'
_diffrn_radiation_monochromator  'plane graphite'
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0617
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -6
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       -7
_diffrn_reflns_limit_l_max       9
_diffrn_reflns_limit_l_min       -5
_diffrn_reflns_number            3328
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         26.495
_diffrn_reflns_theta_min         3.883
_exptl_absorpt_coefficient_mu    9.12
_exptl_absorpt_correction_T_max  0.5842
_exptl_absorpt_correction_T_min  0.3984
_exptl_absorpt_correction_type   integration
_exptl_absorpt_process_details
;
(Coppens & Hamilton, 1970)
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    3.102
_exptl_crystal_description       prism
_exptl_crystal_F_000             186
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.10
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.922
_refine_diff_density_min         -0.743
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.269
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     79
_refine_ls_number_reflns         864
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.269
_refine_ls_R_factor_all          0.0390
_refine_ls_R_factor_gt           0.0321
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0149P)^2^+1.4640P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0806
_refine_ls_wR_factor_ref         0.0844
_reflns_number_gt                782
_reflns_number_total             864
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ku3198sup1.cif
_cod_data_source_block           Mg_SeO4_Na2_SeO4_2H2O
_cod_database_code               2020805
_shelx_hkl_checksum              71398
_shelx_res_checksum              94886
_cod_database_fobs_code 2020805