Crystal Structure and Some Thermodynamic Properties of Ca7MgSi4O16-Bredigite
Bao, Xinjian; He, Mingyue; Zhang, Zhigang; Liu, Xi; Crystals 11 (2020) 14–; doi:10.3390/cryst11010014

data_1566037
_publ_section_title
;
 Crystal Structure and Some Thermodynamic Properties of
 Ca7MgSi4O16-Bredigite
;
_journal_issue                   1
_journal_name_full               Crystals
_journal_page_first              14
_journal_paper_doi               10.3390/cryst11010014
_journal_volume                  11
_journal_year                    2020
_chemical_formula_sum            'Ca7 Mg O16 Si4'
_chemical_formula_weight         673.22
_chemical_name_common            Bredigite
_space_group_IT_number           58
_space_group_name_Hall           '-P 2 2n'
_space_group_name_H-M_alt        'P n n m'
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_H-M   'P n n m'
_atom_sites_solution_hydrogens   none
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   18.3434(17)
_cell_length_b                   6.7313(8)
_cell_length_c                   10.8844(12)
_cell_measurement_reflns_used    1756
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      28.37
_cell_measurement_theta_min      2.18
_cell_volume                     1344.0(3)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device_type  'Bruker Smart Apex II Quazar CCD'
_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  0.0483
_diffrn_reflns_av_sigmaI/netI    0.0455
_diffrn_reflns_limit_h_max       24
_diffrn_reflns_limit_h_min       -24
_diffrn_reflns_limit_k_max       5
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            5549
_diffrn_reflns_theta_full        28.37
_diffrn_reflns_theta_max         28.37
_diffrn_reflns_theta_min         2.18
_exptl_absorpt_coefficient_mu    3.261
_exptl_absorpt_correction_T_max  0.850
_exptl_absorpt_correction_T_min  0.822
_exptl_absorpt_correction_type   multi-scans
_exptl_absorpt_process_details   SADABS
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    3.327
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1344
_exptl_crystal_size_max          0.06
_exptl_crystal_size_mid          0.05
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.876
_refine_diff_density_min         -0.731
_refine_diff_density_rms         0.179
_refine_ls_extinction_coef       0.0005(2)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.004
_refine_ls_hydrogen_treatment    none
_refine_ls_matrix_type           full
_refine_ls_number_parameters     147
_refine_ls_number_reflns         1756
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.004
_refine_ls_R_factor_all          0.0675
_refine_ls_R_factor_gt           0.0472
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0479P)^2^+12.6236P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1157
_refine_ls_wR_factor_ref         0.1289
_reflns_number_gt                1344
_reflns_number_total             1756
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            Crystals-2021-11-1-14.cif
_cod_data_source_block           Bredigite
_cod_original_sg_symbol_H-M      Pnnm
_cod_database_code               1566037