Alkylpyridine Complexes of Tungsten(II) and Chromium(II). First Rotational Isomers of W2X4L4 Molecules with D2 hand D2 Symmetries
F. Albert Cotton; Evgeny V. Dikarev; Jiande Gu; Santiago Herrero; Barbara Modec; Inorganic Chemistry 39 (2000) 5407–5411; doi:10.1021/ic000555v

data_4321561
_publ_section_title
;
 Alkylpyridine Complexes of Tungsten(II) and Chromium(II). First
 Rotational Isomers of W2X4L4 Molecules with D2 hand D2 Symmetries
;
_journal_name_full               'Inorganic Chemistry'
_journal_page_first              5407
_journal_page_last               5411
_journal_paper_doi               10.1021/ic000555v
_journal_volume                  39
_journal_year                    2000
_chemical_compound_source        synthesized
_chemical_formula_analytical     'not measured'
_chemical_formula_moiety         'W2 Cl4 (N C5 H4 C (C H3)3)4'
_chemical_formula_structural     (D2h)-W2Cl4(4-t-Bu-py)4
_chemical_formula_sum            'C36 H52 Cl4 N4 W2'
_chemical_formula_weight         1050.32
_chemical_melting_point          ?
_chemical_name_systematic
; 
 Bis(trans-dichloro-bis(4-tert-butylpyridine))-di-tungsten (II),
 D2h isomer
;
_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           SHELXL
_cell_angle_alpha                68.53(2)
_cell_angle_beta                 72.74(1)
_cell_angle_gamma                85.90(1)
_cell_formula_units_Z            1
_cell_length_a                   8.455(2)
_cell_length_b                   10.004(1)
_cell_length_c                   13.412(2)
_cell_measurement_reflns_used    250
_cell_measurement_temperature    213(2)
_cell_measurement_theta_max      20.8
_cell_measurement_theta_min      8.0
_cell_volume                     1007.3(3)
_computing_cell_refinement       'MADNES (Enraf-Nonius, 1989)'
_computing_data_collection       'MADNES (Enraf-Nonius, 1989)'
_computing_data_reduction        'PROCOR (Kabsch, 1988)'
_computing_molecular_graphics    'SHELXTL V.5 (Siemens, 1994)'
_computing_publication_material  CIFTAB
_computing_structure_refinement  'SHELXL-93 (Sheldrick, 1993)'
_computing_structure_solution    'SHELXTL V.5 (Siemens, 1994)'
_diffrn_ambient_temperature      213(2)
_diffrn_measurement_device       'Nonius FAST area detector'
_diffrn_measurement_method       'Ellipsoid-mask fitting'
_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  0.0434
_diffrn_reflns_av_sigmaI/netI    0.0401
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            4841
_diffrn_reflns_theta_max         22.49
_diffrn_reflns_theta_min         2.24
_diffrn_standards_number         'none (area detector data)'
_exptl_absorpt_coefficient_mu    6.000
_exptl_absorpt_correction_T_max  0.837
_exptl_absorpt_correction_T_min  0.339
_exptl_absorpt_correction_type   'SORTAV (Blessing, 1995)'
_exptl_crystal_colour            dark-violet
_exptl_crystal_density_diffrn    1.731
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    none
_exptl_crystal_description       block-shaped
_exptl_crystal_F_000             512
_exptl_crystal_size_max          0.28
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.10
_refine_diff_density_max         2.166
_refine_diff_density_min         -2.059
_refine_diff_density_rms         0.197
_refine_ls_extinction_coef       noref
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_all   1.059
_refine_ls_goodness_of_fit_obs   1.056
_refine_ls_hydrogen_treatment    noref
_refine_ls_matrix_type           full
_refine_ls_number_parameters     208
_refine_ls_number_reflns         2505
_refine_ls_number_restraints     6
_refine_ls_restrained_S_all      1.060
_refine_ls_restrained_S_obs      1.057
_refine_ls_R_factor_all          0.0376
_refine_ls_R_factor_obs          0.0367
_refine_ls_shift/esd_max         0.000
_refine_ls_shift/esd_mean        0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0679P)^2^+3.6267P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.0949
_refine_ls_wR_factor_obs         0.0932
_reflns_number_observed          2436
_reflns_number_total             2505
_reflns_observed_criterion       >2sigma(I)
_cod_data_source_file            ic000555v_2.cif
_cod_data_source_block           W2Cl4(4-t-Bu-py)4_(1a)
_cod_depositor_comments
;
The following automatic conversions were performed:

'_chemical_melting_point' value 'not measured' was changed to '?' -
the value is undefined or not given.

Automatic conversion script
Id: cif_fix_values 1646 2011-03-28 12:23:43Z adriana 

The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'not measured' was changed to '?'
- the value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc
w=1/[\s^2^(Fo^2^)+(0.0679P)^2^+3.6267P] where P=(Fo^2^+2Fc^2^)/3' was
changed to 'calc'. New tag '_refine_ls_weighting_details' was
created. The value of the new tag was set to
'w=1/[\s^2^(Fo^2^)+(0.0679P)^2^+3.6267P] where P=(Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_database_code               4321561