Revisiting the 1,2,4-triaza-3,5-diborolyl ligand: sigma and pi coordination modes in the alkali metal and rhodium complexes of a planar, 6-pi-electron B2N3- ring.
Ly, Hanh V.; Chow, Joanna H.; Parvez, Masood; McDonald, Robert; Roesler, Roland; Inorganic chemistry 46 (2007) 9303–9311; doi:10.1021/ic7013286

data_4339024
_publ_section_title
;
 Revisiting the 1,2,4-triaza-3,5-diborolyl ligand: sigma and pi
 coordination modes in the alkali metal and rhodium complexes of a planar,
 6-pi-electron B2N3- ring.
;
_journal_issue                   22
_journal_name_full               'Inorganic chemistry'
_journal_page_first              9303
_journal_page_last               9311
_journal_paper_doi               10.1021/ic7013286
_journal_volume                  46
_journal_year                    2007
_chemical_formula_sum            'C14 H17 B2 K N4'
_chemical_formula_weight         302.04
_space_group_IT_number           19
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_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            4
_cell_length_a                   7.746(4)
_cell_length_b                   11.973(4)
_cell_length_c                   16.742(9)
_cell_measurement_temperature    173(2)
_cell_volume                     1552.7(13)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.993
_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  0.0256
_diffrn_reflns_av_sigmaI/netI    0.0375
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            5050
_diffrn_reflns_theta_full        25.03
_diffrn_reflns_theta_max         25.03
_diffrn_reflns_theta_min         3.40
_exptl_absorpt_coefficient_mu    0.338
_exptl_absorpt_correction_T_max  0.9866
_exptl_absorpt_correction_T_min  0.9605
_exptl_crystal_density_diffrn    1.292
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             632
_exptl_crystal_size_max          0.12
_exptl_crystal_size_mid          0.08
_exptl_crystal_size_min          0.04
_refine_diff_density_max         0.259
_refine_diff_density_min         -0.293
_refine_diff_density_rms         0.045
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.05(5)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.056
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     193
_refine_ls_number_reflns         2711
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.056
_refine_ls_R_factor_all          0.0466
_refine_ls_R_factor_gt           0.0379
_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^)+(0.0560P)^2^+0.4500P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0952
_refine_ls_wR_factor_ref         0.1014
_reflns_number_gt                2410
_reflns_number_total             2711
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ic7013286-file004.cif
_cod_data_source_block           2c
_cod_database_code               4339024