[CrBr~2~(NH~3~)~4~][CrBr~4~(NH~3~)~2~], a new chromium(III) complex
Stork, Ludwig; Liu, Xiaohui; Fokwa, Boniface P. T.; Dronskowski, Richard; Acta Crystallographica Section C 65 (2009) i54–i56; doi:10.1107/S0108270109027218

data_2017268
_publ_section_title
;
 [CrBr~2~(NH~3~)~4~][CrBr~4~(NH~3~)~2~], a new chromium(III) complex
;
_journal_coeditor_code           SQ3202
_journal_issue                   8
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              i54
_journal_page_last               i56
_journal_paper_doi               10.1107/S0108270109027218
_journal_volume                  65
_journal_year                    2009
_chemical_formula_iupac          '[Cr Br2 (N H3)4] [Cr Br4 (N H3)2]'
_chemical_formula_moiety         'Br2 Cr H12 N4 + , Br4 Cr H6 N2 -'
_chemical_formula_sum            'Br6 Cr2 H18 N6'
_chemical_formula_weight         685.66
_chemical_name_systematic
;
<i>trans</i>-tetraamminedibromidochromium(III)
<i>trans</i>-diamminetetrabromidochromate(III)
;
_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_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL97
_cell_angle_alpha                86.184(2)
_cell_angle_beta                 87.300(2)
_cell_angle_gamma                84.293(2)
_cell_formula_units_Z            1
_cell_length_a                   5.9697(5)
_cell_length_b                   6.8410(5)
_cell_length_c                   9.9092(8)
_cell_measurement_reflns_used    4174
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      28.34
_cell_measurement_theta_min      3.00
_cell_volume                     401.45(6)
_computing_cell_refinement       'SAINT (Bruker, 2007)'
_computing_data_collection       'SMART (Bruker, 2007)'
_computing_data_reduction        'SAINT (Bruker, 2007)'
_computing_molecular_graphics    'PLATON (Spek, 2003)'
_computing_publication_material  'enCIFer (Allen <i>et al.</i>,  2004)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.992
_diffrn_measured_fraction_theta_max 0.992
_diffrn_measurement_device_type  'Bruker SMART CCD area-detector'
_diffrn_measurement_method       '\f and \w'
_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  0.0266
_diffrn_reflns_av_sigmaI/netI    0.0347
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       13
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            4174
_diffrn_reflns_theta_full        28.34
_diffrn_reflns_theta_max         28.34
_diffrn_reflns_theta_min         3.00
_exptl_absorpt_coefficient_mu    16.263
_exptl_absorpt_correction_T_max  0.443
_exptl_absorpt_correction_T_min  0.283
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Sheldrick, 1996)'
_exptl_crystal_colour            green
_exptl_crystal_density_diffrn    2.836
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             318
_exptl_crystal_size_max          0.08
_exptl_crystal_size_mid          0.07
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.550
_refine_diff_density_min         -1.048
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.060
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     97
_refine_ls_number_reflns         1992
_refine_ls_number_restraints     15
_refine_ls_restrained_S_all      1.058
_refine_ls_R_factor_all          0.0301
_refine_ls_R_factor_gt           0.0254
_refine_ls_shift/su_max          0.005
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w = 1/[\s^2^(Fo^2^)+(0.0310P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0593
_refine_ls_wR_factor_ref         0.0605
_reflns_number_gt                1764
_reflns_number_total             1992
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            sq3202.cif
_cod_data_source_block           I
_cod_database_code               2017268
_cod_database_fobs_code          2017268