Are J(Si-H) NMR Coupling Constants Really a Probe for the Existence of Nonclassical H-Si Interactions?
Stuart R. Dubberley; Stanislav K. Ignatov; Nicholas H. Rees; Alexei G. Razuvaev; Philip Mountford; Georgii I. Nikonov; Journal of the American Chemical Society 125 (2003) 642–643; doi:10.1021/ja027935v

data_4113393
_publ_contact_author
; Dr Georgii I. Nikonov
  Department of Chemistry, Moscow State University
  Vorob'evy Gory, Moscow 119899, Russia
;
_publ_contact_author_email       nikonov@org.chem.msu.su
_publ_section_title
;
 Are J(Si-H) NMR Coupling Constants Really a Probe for the Existence of
 Nonclassical H-Si Interactions?
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              642
_journal_page_last               643
_journal_paper_doi               10.1021/ja027935v
_journal_volume                  125
_journal_year                    2003
_chemical_formula_sum            'C21 H35 Cl2 N P Si Ta'
_chemical_formula_weight         612.41
_chemical_name_systematic
; 
 (cyclopentadienyl)(2,6-diisopropylphenylimido)(trimethylphosphine)
(dimethylchlorosilyl)(hydrido) tantalum (V)
;
_space_group_IT_number           61
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2ac 2ab'
_symmetry_space_group_name_H-M   'P b c a'
_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            8
_cell_length_a                   16.331(3)
_cell_length_b                   17.298(4)
_cell_length_c                   17.968(4)
_cell_measurement_temperature    293(2)
_cell_volume                     5075.8(19)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.904
_diffrn_measured_fraction_theta_max 0.904
_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  0.0000
_diffrn_reflns_av_sigmaI/netI    0.0241
_diffrn_reflns_limit_h_max       21
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       22
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       23
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            5773
_diffrn_reflns_theta_full        27.48
_diffrn_reflns_theta_max         27.48
_diffrn_reflns_theta_min         5.11
_exptl_absorpt_coefficient_mu    4.659
_exptl_crystal_density_diffrn    1.603
_exptl_crystal_F_000             2432
_refine_diff_density_max         2.847
_refine_diff_density_min         -0.873
_refine_diff_density_rms         0.112
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.998
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     309
_refine_ls_number_reflns         5773
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.998
_refine_ls_R_factor_all          0.0441
_refine_ls_R_factor_gt           0.0349
_refine_ls_shift/su_max          13.088
_refine_ls_shift/su_mean         0.084
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0463P)^2^+24.9671P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0955
_refine_ls_wR_factor_ref         0.1008
_reflns_number_gt                4862
_reflns_number_total             5773
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja027935v-7_s2.cif
_cod_data_source_block           gin
_cod_depositor_comments
;
The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc
w=1/[\s^2^(Fo^2^)+(0.0463P)^2^+24.9671P] 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^)+(0.0463P)^2^+24.9671P] where P=(Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_cell_volume        5075.9(18)
_cod_database_code               4113393