Re-investigation of Cd~2~B~2~O~5~: evidence of a centre of symmetry
Weil, Matthias; Acta Crystallographica Section E 59 (2003) i95–i97; doi:10.1107/S1600536803012157

data_2202291
_publ_section_title
;
 Re-investigation of Cd~2~B~2~O~5~: evidence of a centre of symmetry
;
_journal_issue                   7
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              i95
_journal_page_last               i97
_journal_paper_doi               10.1107/S1600536803012157
_journal_volume                  59
_journal_year                    2003
_chemical_formula_iupac          'Cd2 (B2 O5)'
_chemical_formula_structural     'Cd2 (B2 O5)'
_chemical_formula_sum            'B2 Cd2 O5'
_chemical_formula_weight         326.42
_chemical_name_common            'Cadmium pyroborate'
_chemical_name_systematic        'Cadmium diborate'
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_primary     isomor
_audit_creation_method           SHELXL-97
_cell_angle_alpha                105.441(8)
_cell_angle_beta                 90.807(6)
_cell_angle_gamma                91.933(6)
_cell_formula_units_Z            2
_cell_length_a                   3.4490(2)
_cell_length_b                   6.3603(5)
_cell_length_c                   9.9502(8)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      14.851
_cell_measurement_theta_min      12.353
_cell_volume                     210.22(3)
_computing_cell_refinement       'CAD-4 Software'
_computing_data_collection       'CAD-4 Software (Nonius, 1989)'
_computing_data_reduction        'HELENA implemented in PLATON (Spek, 2003)'
_computing_molecular_graphics    'ATOMS (Dowty, 2000)'
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device_type  'Enraf-Nonius CAD-4 diffractometer'
_diffrn_measurement_method       \w/2\q
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0176
_diffrn_reflns_av_sigmaI/netI    0.0198
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -6
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            5166
_diffrn_reflns_theta_full        39.94
_diffrn_reflns_theta_max         39.94
_diffrn_reflns_theta_min         2.12
_diffrn_standards_decay_%        0
_diffrn_standards_interval_time  500
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    10.024
_exptl_absorpt_correction_T_max  0.4726
_exptl_absorpt_correction_T_min  0.2670
_exptl_absorpt_correction_type   numerical
_exptl_absorpt_process_details
;
The crystal shape was optimized by minimizing the R-value of
selected \y-scanned reflections using the program HABITUS (Herrendorf,
1993-97). The habit so derived was used for the numerical absorption
correction.
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    5.157
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             292
_exptl_crystal_size_max          0.22
_exptl_crystal_size_mid          0.14
_exptl_crystal_size_min          0.07
_refine_diff_density_max         2.333
_refine_diff_density_min         -2.032
_refine_ls_extinction_coef       0.238(4)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL97 (Sheldrick, 1997)'
_refine_ls_goodness_of_fit_ref   1.125
_refine_ls_matrix_type           full
_refine_ls_number_parameters     83
_refine_ls_number_reflns         2584
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.125
_refine_ls_R_factor_all          0.0229
_refine_ls_R_factor_gt           0.0215
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.0307P)^2^+0.3225P] where P = (Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0552
_refine_ls_wR_factor_ref         0.0558
_reflns_number_gt                2464
_reflns_number_total             2584
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            br6105.cif
_cod_data_source_block           I
_cod_database_code               2202291
_cod_database_fobs_code          2202291