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_7013663
_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            'C70 H86 Mo4 N6 O26'
_chemical_formula_weight         1811.21
_chemical_name_common
;
Tetra(N-methylcollidinium)
octaoxotetrasquaratotetramolybdate(V) methanol collidine (4/1/2/2)
;
_chemical_name_systematic
;
Tetra(N-methylcollidinium) octaoxotetrasquaratotetramolybdate(V)
methanol collidine (4/1/2/2)
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 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                 100.0820(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   14.2914(6)
_cell_length_b                   17.1820(8)
_cell_length_c                   30.5418(14)
_cell_measurement_temperature    90(2)
_cell_volume                     7383.9(6)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      90(2)
_diffrn_detector_area_resol_mean '512 x 512'
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'CCD detector'
_diffrn_measurement_method       'Phi and omega scans'
_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  0.0758
_diffrn_reflns_av_sigmaI/netI    0.0763
_diffrn_reflns_limit_h_max       20
_diffrn_reflns_limit_h_min       -21
_diffrn_reflns_limit_k_max       25
_diffrn_reflns_limit_k_min       -24
_diffrn_reflns_limit_l_max       44
_diffrn_reflns_limit_l_min       -44
_diffrn_reflns_number            95337
_diffrn_reflns_theta_full        31.51
_diffrn_reflns_theta_max         31.51
_diffrn_reflns_theta_min         1.49
_exptl_absorpt_coefficient_mu    0.749
_exptl_absorpt_correction_T_max  0.9426
_exptl_absorpt_correction_T_min  0.8897
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS SHELXL-97 (Sheldrick, 1997)'
_exptl_crystal_colour            orange
_exptl_crystal_density_diffrn    1.629
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             3696
_exptl_crystal_size_max          0.16
_exptl_crystal_size_mid          0.10
_exptl_crystal_size_min          0.08
_refine_diff_density_max         0.949
_refine_diff_density_min         -0.964
_refine_diff_density_rms         0.132
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.011
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     958
_refine_ls_number_reflns         24562
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.011
_refine_ls_R_factor_all          0.0919
_refine_ls_R_factor_gt           0.0514
_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^)+(0.0425P)^2^+4.2000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1015
_refine_ls_wR_factor_ref         0.1163
_reflns_number_gt                16327
_reflns_number_total             24562
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b311348e.txt
_cod_data_source_block           2a
_cod_original_sg_symbol_H-M      'P 21/n'
_cod_database_code               7013663