Chemical Twinning in Zintl Phases
Fabio Zürcher; Steffen Wengert; Reinhard Nesper; Inorganic Chemistry 38 (1999) 4567–4569; doi:10.1021/ic990147v

data_4322259
_publ_section_title
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 Chemical Twinning in Zintl Phases
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_journal_name_full               'Inorganic Chemistry'
_journal_page_first              4567
_journal_page_last               4569
_journal_paper_doi               10.1021/ic990147v
_journal_volume                  38
_journal_year                    1999
_chemical_formula_moiety         BaMg4Si3
_chemical_formula_sum            'Ba Mg4 Si3'
_chemical_formula_weight         318.85
_chemical_name_systematic
; 
 ? 
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_space_group_IT_number           123
_symmetry_cell_setting           tetragonal
_symmetry_space_group_name_Hall  '-P 4 2'
_symmetry_space_group_name_H-M   'P 4/m m m'
_atom_sites_solution_hydrogens   geom
_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            1
_cell_length_a                   4.6115(9)
_cell_length_b                   4.6115(9)
_cell_length_c                   8.615(2)
_cell_measurement_reflns_used    2000
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      24
_cell_measurement_theta_min      4
_cell_volume                     183.21(7)
_computing_cell_refinement       'SELECT and CELL (STOE)'
_computing_data_collection       'EXPOSE (STOE)'
_computing_data_reduction        'INTEGRATE (STOE)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.958
_diffrn_measured_fraction_theta_max 0.958
_diffrn_measurement_device_type  'STOE IPSD'
_diffrn_measurement_method       Oscillation
_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  0.0591
_diffrn_reflns_av_sigmaI/netI    0.0216
_diffrn_reflns_limit_h_max       5
_diffrn_reflns_limit_h_min       -5
_diffrn_reflns_limit_k_max       5
_diffrn_reflns_limit_k_min       -5
_diffrn_reflns_limit_l_max       9
_diffrn_reflns_limit_l_min       -9
_diffrn_reflns_number            1019
_diffrn_reflns_theta_full        23.87
_diffrn_reflns_theta_max         23.87
_diffrn_reflns_theta_min         4.42
_exptl_absorpt_coefficient_mu    6.135
_exptl_absorpt_correction_type   'not measured'
_exptl_crystal_colour            black
_exptl_crystal_density_diffrn    2.890
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       regulus
_exptl_crystal_F_000             146
_exptl_crystal_size_max          0.1
_exptl_crystal_size_mid          0.1
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.453
_refine_diff_density_min         -0.532
_refine_diff_density_rms         0.108
_refine_ls_extinction_coef       0.051(10)
_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   1.175
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     13
_refine_ls_number_reflns         114
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.175
_refine_ls_R_factor_all          0.0166
_refine_ls_R_factor_gt           0.0166
_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^)+(0.0150P)^2^+0.4384P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0402
_refine_ls_wR_factor_ref         0.0402
_reflns_number_gt                114
_reflns_number_total             114
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ic990147v_1.cif
_cod_data_source_block           bamg4si3
_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_original_cell_volume        183.21(6)
_cod_database_code               4322259