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

data_4322260
_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         BaMg4Ge3
_chemical_formula_sum            'Ba Ge3 Mg4'
_chemical_formula_weight         452.35
_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
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            1
_cell_length_a                   4.6335(8)
_cell_length_b                   4.6335(8)
_cell_length_c                   8.746(2)
_cell_measurement_reflns_used    122
_cell_measurement_temperature    298(2)
_cell_measurement_theta_max      18
_cell_measurement_theta_min      5
_cell_volume                     187.77(6)
_computing_cell_refinement       DIF4
_computing_data_collection       DIF4
_computing_data_reduction        REDU4
_computing_structure_refinement  'SHELXL-96 (Sheldrick, 1996)'
_computing_structure_solution    'SHELXS-96 (Sheldrick, 1990)'
_diffrn_ambient_temperature      298(2)
_diffrn_measurement_device       'STOE STADI4'
_diffrn_measurement_method       'omega-theta scan'
_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  0.0487
_diffrn_reflns_av_sigmaI/netI    0.0231
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -6
_diffrn_reflns_limit_k_max       6
_diffrn_reflns_limit_k_min       -6
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            1196
_diffrn_reflns_theta_max         29.97
_diffrn_reflns_theta_min         2.33
_diffrn_standards_interval_time  180
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    17.282
_exptl_absorpt_correction_T_max  0.0765
_exptl_absorpt_correction_T_min  0.0405
_exptl_absorpt_correction_type   'empirical (psi-scan)'
_exptl_crystal_colour            black
_exptl_crystal_density_diffrn    4.000
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       regulus
_exptl_crystal_F_000             200
_exptl_crystal_size_max          0.15
_exptl_crystal_size_mid          0.15
_exptl_crystal_size_min          0.10
_refine_diff_density_max         1.233
_refine_diff_density_min         -2.234
_refine_diff_density_rms         0.300
_refine_ls_extinction_coef       0.046(5)
_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_all   1.146
_refine_ls_goodness_of_fit_obs   1.166
_refine_ls_matrix_type           full
_refine_ls_number_parameters     13
_refine_ls_number_reflns         206
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.146
_refine_ls_restrained_S_obs      1.166
_refine_ls_R_factor_all          0.0231
_refine_ls_R_factor_obs          0.0221
_refine_ls_shift/esd_max         0.000
_refine_ls_shift/esd_mean        0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0377P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.0545
_refine_ls_wR_factor_obs         0.0541
_reflns_number_observed          197
_reflns_number_total             206
_reflns_observed_criterion       >2sigma(I)
_cod_data_source_file            ic990147v_2.cif
_cod_data_source_block           bamg4ge3
_cod_depositor_comments
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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 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc
w=1/[\s^2^(Fo^2^)+(0.0377P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3' was
changed to 'calc'. New tag '_refine_ls_weighting_details' was
created. The value of the new tag was set to
'w=1/[\s^2^(Fo^2^)+(0.0377P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
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_cod_original_cell_volume        187.77(7)
_cod_database_code               4322260