Refinement of the crystal structure of dibarium tetrasilicide, Ba2Si4
Thorsten Goebel; Yurii Prots; Frank Haarmann; Zeitschrift für Kristallographie - New Crystal Structures 224 (2009) 7–; doi:

data_8103005
_publ_section_title
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 Refinement of the crystal structure of dibarium tetrasilicide, Ba2Si4
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_journal_issue                   1
_journal_name_full
'Zeitschrift f\"ur Kristallographie - New Crystal Structures'
_journal_page_first              7
_journal_volume                  224
_journal_year                    2009
_chemical_formula_sum            'Ba2 Si4'
_chemical_formula_weight         387.0
_space_group_IT_number           62
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2ac 2n'
_symmetry_space_group_name_H-M   'P n m a'
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_date             2008-06-18T12:00:00-00:00
_audit_creation_method           'WinGX routine CIF_UPDATE'
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.9326(4)
_cell_length_b                   6.7262(2)
_cell_length_c                   11.5335(5)
_cell_measurement_temperature    295(2)
_cell_volume                     692.96(5)
_computing_cell_refinement       'CSD (Akselrud, 1993)'
_computing_data_collection       'CrystalClear (Rigaku Corp., 2000)'
_computing_data_reduction        'CrystalClear (Rigaku Corp., 2000)'
_computing_structure_refinement  ???????????
_diffrn_ambient_temperature      295.15
_diffrn_detector_area_resol_mean 14.6306
_diffrn_measurement_details
;
scan:
 Number of images: 400
            Slice: -120.0000 - 120.0000
      Image width: 0.6000
         Exp time: 30.0000
    Rotation axis: Phi
            Omega: 0.0000
              Chi: 0.0000
              Phi: 0.0000
              XTD: 41.7400
           2theta: -25.0000
scan:
 Number of images: 95
            Slice: -38.0000 - 19.0000
      Image width: 0.6000
         Exp time: 30.0000
    Rotation axis: Omega
            Omega: 0.0000
              Chi: -90.0000
              Phi: -5.0000
              XTD: 41.7400
           2theta: -25.0000
;
_diffrn_measurement_device       'Rigaku AFC7'
_diffrn_measurement_method       oscillation
_diffrn_radiation_detector       'Mercury CCD'
_diffrn_radiation_monochromator  'Graphite Monochromator'
_diffrn_radiation_source         'Sealed Tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.7107
_diffrn_reflns_av_R_equivalents  0.021
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -7
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            6791
_diffrn_reflns_reduction_process 'Lp corrections applied'
_diffrn_reflns_theta_max         31.50
_diffrn_reflns_theta_min         2.88
_diffrn_source_current           32.0000
_diffrn_source_power             1.6000
_diffrn_source_voltage           50.0000
_exptl_absorpt_coefficient_mu    11.86
_exptl_absorpt_correction_T_max  1.0000
_exptl_absorpt_correction_T_min  0.5624
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            black
_exptl_crystal_density_diffrn    3.71
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       'irregular shaped'
_exptl_crystal_F_000             672
_exptl_crystal_size_max          0.120
_exptl_crystal_size_mid          0.050
_exptl_crystal_size_min          0.045
_refine_diff_density_max         2.181
_refine_diff_density_min         -1.464
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.264
_refine_ls_matrix_type           full
_refine_ls_number_parameters     34
_refine_ls_number_reflns         1234
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.264
_refine_ls_R_factor_all          0.026
_refine_ls_R_factor_gt           0.025
_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^(Fo2^)+(0.0065P)2^+3.7087P] where P=(Fo2^+2Fc2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.044
_refine_ls_wR_factor_ref         0.044
_reflns_number_gt                1178
_reflns_number_total             1234
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            409973.cff
_cod_data_source_block           global
_cod_depositor_comments
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The following automatic conversions were performed:
'_exptl_absorpt_correction_type' value 'Multi-scan' changed to
'multi-scan' according to
'/home/saulius/struct/CIF-dictionaries/cif_core.dic' dictionary named
'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1555 2011-01-17 13:19:09Z saulius 
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_cod_database_code               8103005