Niobocene hydrides with functionalised silyl ligands. Tuning of interligand hypervalent interactions (IHI) M‒H →Si‒X
Nikonov, Georgii I.; Kuzmina, Lyudmila G.; Howard, Judith A. K.; Journal of the Chemical Society, Dalton Transactions  (2002) 3037–; doi:10.1039/b110998g

data_7011351
_publ_section_title
;
 Niobocene hydrides with functionalised silyl ligands. Tuning of
 interligand hypervalent interactions (IHI) M--H \\rightarrow Si--X
;
_journal_issue                   15
_journal_name_full
'Journal of the Chemical Society, Dalton Transactions'
_journal_page_first              3037
_journal_paper_doi               10.1039/b110998g
_journal_year                    2002
_chemical_formula_moiety         Cp2Nb(SiMe2I)2H
_chemical_formula_sum            'C14 H23 I2 Nb Si2'
_chemical_formula_weight         594.21
_chemical_name_systematic
; 
bis(cyclopentadienyl)bis(iododimethylsilyl)hydrido niobium(V) 
;
_space_group_IT_number           87
_symmetry_cell_setting           tetragonal
_symmetry_space_group_name_Hall  '-I 4'
_symmetry_space_group_name_H-M   'I 4/m'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   18.996(3)
_cell_length_b                   18.996(3)
_cell_length_c                   13.031(3)
_cell_measurement_temperature    173(2)
_cell_volume                     4702.2(15)
_computing_structure_refinement  'SHELXL-93 (Sheldrick, 1993)'
_computing_structure_solution    'SHELXS-86 (Sheldrick, 1990)'
_diffrn_ambient_temperature      173(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  0.0000
_diffrn_reflns_av_sigmaI/netI    0.0292
_diffrn_reflns_limit_h_max       -6
_diffrn_reflns_limit_h_min       -24
_diffrn_reflns_limit_k_max       23
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            1417
_diffrn_reflns_theta_max         25.97
_diffrn_reflns_theta_min         6.44
_exptl_absorpt_coefficient_mu    3.230
_exptl_absorpt_correction_T_max  0.977
_exptl_absorpt_correction_T_min  0.708
_exptl_absorpt_correction_type   empirical
_exptl_crystal_colour            dark-violet
_exptl_crystal_density_diffrn    1.679
_exptl_crystal_F_000             2256
_exptl_crystal_size_max          0.44
_exptl_crystal_size_mid          0.36
_exptl_crystal_size_min          0.26
_refine_diff_density_max         1.086
_refine_diff_density_min         -0.768
_refine_diff_density_rms         0.148
_refine_ls_extinction_coef       0.0003(3)
_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   1.115
_refine_ls_goodness_of_fit_obs   1.190
_refine_ls_matrix_type           full
_refine_ls_number_parameters     99
_refine_ls_number_reflns         1417
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.115
_refine_ls_restrained_S_obs      1.190
_refine_ls_R_factor_all          0.0736
_refine_ls_R_factor_obs          0.0560
_refine_ls_shift/esd_max         0.003
_refine_ls_shift/esd_mean        0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.1040P)^2^+52.3760P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.1758
_refine_ls_wR_factor_obs         0.1658
_reflns_number_observed          1122
_reflns_number_total             1417
_reflns_observed_criterion       >2sigma(I)
_cod_data_source_file            b110998g.txt
_cod_data_source_block           compound16
_cod_depositor_comments
;
The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc
w=1/[\s^2^(Fo^2^)+(0.1040P)^2^+52.3760P] 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^)+(0.1040P)^2^+52.3760P] 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        4702.2(13)
_cod_original_sg_symbol_H-M      I4/m
_cod_database_code               7011351