Tetranuclear vanadium(III) carboxylate chemistry, and a new example of a metal butterfly complex exhibiting spin frustration: structure and properties of [V~4~O~2~(O~2~CEt)~7~(bpy)~2~](ClO~4~)
Castro, Stephanie L.; Sun, Ziming; Bollinger, John C.; Hendrickson, David N.; Christou, George; Journal of the Chemical Society, Chemical Communications  (1995) 2517–2548; doi:10.1039/C39950002517

data_5000309
_publ_section_title
;
 Tetranuclear vanadium(III) carboxylate chemistry, and a new example of a
 metal butterfly complex exhibiting spin frustration: structure and
 properties of [V~4~O~2~(O~2~CEt)~7~(bpy)~2~](ClO~4~)
;
_journal_issue                   24
_journal_name_full
;
 Journal of the Chemical Society, Chemical Communications
;
_journal_page_first              2517
_journal_page_last               2548
_journal_paper_doi               10.1039/C39950002517
_journal_year                    1995
_chemical_formula_sum            'C43 H55 Cl5 N4 O20 V4'
_chemical_formula_weight         1328.92
_space_group_IT_number           2
_space_group_name_Hall           '-P 1'
_space_group_name_H-M_alt        'P -1'
_symmetry_cell_setting           triclinic
_symmetry_Int_Tables_number      2
_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           SHELXL
_cell_angle_alpha                87.510(10)
_cell_angle_beta                 96.650(10)
_cell_angle_gamma                86.660(10)
_cell_formula_units_Z            2
_cell_length_a                   13.302(4)
_cell_length_b                   13.265(4)
_cell_length_c                   15.905(5)
_cell_measurement_temperature    293(2)
_cell_volume                     2779.3(15)
_computing_structure_refinement  'SHELXL-93 (Sheldrick, 1993)'
_computing_structure_solution    'SHELXS-86 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_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  0.0400
_diffrn_reflns_av_sigmaI/netI    0.0701
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            12313
_diffrn_reflns_theta_max         22.50
_diffrn_reflns_theta_min         3.07
_exptl_absorpt_coefficient_mu    0.968
_exptl_crystal_density_diffrn    1.588
_exptl_crystal_F_000             1356
_refine_diff_density_max         1.465
_refine_diff_density_min         -0.810
_refine_diff_density_rms         0.145
_refine_ls_extinction_coef       0.0012(6)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_all   1.858
_refine_ls_goodness_of_fit_obs   2.059
_refine_ls_hydrogen_treatment    ?
_refine_ls_matrix_type           full
_refine_ls_number_parameters     906
_refine_ls_number_reflns         7249
_refine_ls_number_restraints     456
_refine_ls_restrained_S_all      1.827
_refine_ls_restrained_S_obs      1.989
_refine_ls_R_factor_all          0.0905
_refine_ls_R_factor_obs          0.0716
_refine_ls_shift/esd_max         -0.957
_refine_ls_shift/esd_mean        0.046
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_scheme
; calc
 [1.00000+0.00000exp(0.00(sin\q/\l)^2^)]/
   [\s^2^(Fo^2^)+0.0000+0.0000*P+(0.0400P)^2^+0.0000sin\q/\l]
 where P = 1.00000Fo^2^ + 0.00000Fc^2^
;
_refine_ls_wR_factor_all         0.1719
_refine_ls_wR_factor_obs         0.1649
_reflns_number_observed          5730
_reflns_number_total             7256
_reflns_observed_criterion       >2sigma(I)
_cod_database_code               5000309