Structures and optical properties of two phases of SrMgF4.
Yelisseyev, Alexander P.; Jiang, Xingxing; Isaenko, Ludmila I.; Kang, Lei; Bai, Lei; Lin, Zheshuai; Goloshumova, Alina A.; Lobanov, Sergei I.; Naumov, Dmitry Y.; Physical chemistry chemical physics : PCCP 17 (2015) 500–508; doi:10.1039/c4cp04689g

data_7218678
_publ_section_title
;
 Structures and optical properties of two phases of SrMgF4.
;
_journal_issue                   1
_journal_name_full               'Physical chemistry chemical physics : PCCP'
_journal_page_first              500
_journal_page_last               508
_journal_paper_doi               10.1039/c4cp04689g
_journal_volume                  17
_journal_year                    2015
_chemical_absolute_configuration ad
_chemical_formula_moiety         'F4 Mg Sr'
_chemical_formula_sum            'F4 Mg Sr'
_chemical_formula_weight         187.93
_space_group_IT_number           4
_symmetry_cell_setting           monoclinic
_symmetry_Int_Tables_number      4
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 1'
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 105.030(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            12
_cell_length_a                   7.4736(5)
_cell_length_b                   16.8835(12)
_cell_length_c                   7.8010(5)
_cell_measurement_reflns_used    4496
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      36.30
_cell_measurement_theta_min      2.82
_cell_volume                     950.66(11)
_computing_cell_refinement       'SAINT (Bruker, 2004)'
_computing_data_collection       'APEX2 (Bruker, 2004)'
_computing_data_reduction        'SAINT (Bruker, 2004)'
_computing_molecular_graphics    'SHELXTL (Bruker, 2004)'
_computing_publication_material  'SHELXTL (Bruker, 2004)'
_computing_structure_refinement  'SHELXTL (Bruker, 2004)'
_computing_structure_solution    'SHELXTL (Bruker, 2004)'
_diffrn_ambient_temperature      150(2)
_diffrn_detector_area_resol_mean 25
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker Nonius X8Apex CCD area-detector'
_diffrn_measurement_method       '\f scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0322
_diffrn_reflns_av_sigmaI/netI    0.0670
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       22
_diffrn_reflns_limit_k_min       -22
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -10
_diffrn_reflns_number            11895
_diffrn_reflns_theta_full        28.28
_diffrn_reflns_theta_max         28.28
_diffrn_reflns_theta_min         2.41
_diffrn_source                   'fine-focus sealed tube'
_diffrn_standards_decay_%        0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    17.130
_exptl_absorpt_correction_T_max  0.2615
_exptl_absorpt_correction_T_min  0.1410
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS (Bruker, 2004)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    3.939
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             1032
_exptl_crystal_size_max          0.19
_exptl_crystal_size_mid          0.13
_exptl_crystal_size_min          0.11
_refine_diff_density_max         0.765
_refine_diff_density_min         -0.730
_refine_diff_density_rms         0.133
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.008(5)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.870
_refine_ls_hydrogen_treatment    noref
_refine_ls_matrix_type           full
_refine_ls_number_parameters     325
_refine_ls_number_reflns         4694
_refine_ls_number_restraints     13
_refine_ls_restrained_S_all      0.867
_refine_ls_R_factor_all          0.0321
_refine_ls_R_factor_gt           0.0235
_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^)+(0.0000P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0560
_refine_ls_wR_factor_ref         0.0604
_reflns_number_gt                4017
_reflns_number_total             4694
_reflns_threshold_expression     >2\s(I)
_cod_data_source_file            c4cp04689g2.cif
_cod_data_source_block           is_low
_cod_depositor_comments
'Adding full bibliography for 7218677--7218678.cif.'
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               7218678