Novel molybdenum(V) squarato complexes based on the dinuclear metal‒metal bonded unit: syntheses and structural characterization of dinuclear [Mo2O4(C4O4)(R-Py)4] and tetranuclear [Mo4O8(C4O4)4]4−
Barbara Modec; Jurij V. Brenčič; Eric M. Burkholder; Jon Zubieta; Dalton Trans.  (2003) 4618–4625; doi:10.1039/b311348e

data_7013664
_publ_section_title
;
 Novel molybdenum(V) squarato complexes based on the dinuclear
 metal--metal bonded unit: syntheses and structural characterization of
 dinuclear [Mo2O4(C4O4)(R-Py)4] and tetranuclear
 [Mo4O8(C4O4)4]4&#x2212;
;
_journal_issue                   24
_journal_name_full               'Dalton Trans.'
_journal_page_first              4618
_journal_page_last               4625
_journal_paper_doi               10.1039/b311348e
_journal_year                    2003
_chemical_formula_sum            'C55 H58 Br Mo4 N5 O24'
_chemical_formula_weight         1636.73
_chemical_name_common
;Tetracollidinium N-ethylpyridinium
octaoxotetrasquaratotetramolybdate(V) bromide
;
_chemical_name_systematic
;
Tetracollidinium N-ethylpyridinium octaoxotetrasquaratotetramolybdate(V)
bromide
;
_space_group_IT_number           11
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yb'
_symmetry_space_group_name_H-M   'P 1 21/m 1'
_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                 96.0427(4)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   11.05280(10)
_cell_length_b                   22.6688(2)
_cell_length_c                   12.1180(2)
_cell_measurement_temperature    150(2)
_cell_volume                     3019.34(6)
_computing_cell_refinement       'Denzo-SMN (Otwinowski & Minor, 1997)'
_computing_data_collection       'Denzo-SMN (Otwinowski & Minor, 1997)'
_computing_data_reduction        'Denzo-SMN (Otwinowski & Minor, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      150(2)
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.993
_diffrn_measurement_device_type  'Nonius Kappa CCD diffractometer'
_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  0.0168
_diffrn_reflns_av_sigmaI/netI    0.0274
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       26
_diffrn_reflns_limit_k_min       -26
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            10451
_diffrn_reflns_theta_full        25.04
_diffrn_reflns_theta_max         25.04
_diffrn_reflns_theta_min         3.18
_exptl_absorpt_coefficient_mu    1.560
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            orange
_exptl_crystal_density_diffrn    1.800
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1636
_exptl_crystal_size_max          0.25
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.18
_refine_diff_density_max         2.039
_refine_diff_density_min         -0.590
_refine_diff_density_rms         0.081
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.072
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     418
_refine_ls_number_reflns         5462
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.072
_refine_ls_R_factor_all          0.0301
_refine_ls_R_factor_gt           0.0255
_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^(Fo^2^)+(0.0253P)^2^+4.9927P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0637
_refine_ls_wR_factor_ref         0.0665
_reflns_number_gt                4925
_reflns_number_total             5462
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b311348e.txt
_cod_data_source_block           2b
_cod_original_sg_symbol_H-M      'P 21/m'
_cod_database_code               7013664