Homo- and Cross-[2+2]-Cycloaddition of 1,1-Diphenylsilene and 1,1-Diphenylgermene. Absolute Rate Constants for Dimerization and the Molecular Structures and Photochemistry of the Resulting 1,3-Dimetallacyclobutanes
Toltl, Nicholas P.; Stradiotto, Mark; Morkin, Tracy L.; Leigh, William J.; Organometallics 18 (1999) 5643–; doi:10.1021/om990447k

data_4077811
_publ_section_title
;
 Homo- and Cross-[2+2]-Cycloaddition of 1,1-Diphenylsilene and
 1,1-Diphenylgermene. Absolute Rate Constants for Dimerization and the
 Molecular Structures and Photochemistry of the Resulting
 1,3-Dimetallacyclobutanes
;
_journal_issue                   26
_journal_name_full               Organometallics
_journal_page_first              5643
_journal_paper_doi               10.1021/om990447k
_journal_volume                  18
_journal_year                    1999
_chemical_formula_sum            'C26 H24 Si2'
_chemical_formula_weight         392.63
_space_group_IT_number           15
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-C 2yc'
_symmetry_space_group_name_H-M   'C 1 2/c 1'
_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                 97.2060(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   20.5430(2)
_cell_length_b                   6.1256(2)
_cell_length_c                   17.8378(3)
_cell_measurement_reflns_used    64
_cell_measurement_temperature    300(2)
_cell_measurement_theta_max      22.49
_cell_measurement_theta_min      2.00
_cell_volume                     2226.95(8)
_computing_structure_refinement  'SHELXL-V.5.03 (Sheldrick, 1994)'
_computing_structure_solution    'SHELXTL-V.5.03 (Sheldrick, 1994)'
_diffrn_ambient_temperature      300(2)
_diffrn_measurement_device_type  'Siemems Smart CCD'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'rotating anode'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0511
_diffrn_reflns_av_sigmaI/netI    0.0420
_diffrn_reflns_limit_h_max       26
_diffrn_reflns_limit_h_min       -26
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       -5
_diffrn_reflns_limit_l_max       23
_diffrn_reflns_limit_l_min       -23
_diffrn_reflns_number            6265
_diffrn_reflns_theta_max         22.49
_diffrn_reflns_theta_min         2.00
_exptl_absorpt_coefficient_mu    0.168
_exptl_absorpt_correction_T_max  0.978
_exptl_absorpt_correction_T_min  0.453
_exptl_absorpt_correction_type   'SADABS (Sheldrick, 1996)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.171
_exptl_crystal_description       plate
_exptl_crystal_F_000             832
_exptl_crystal_size_max          0.34
_exptl_crystal_size_mid          0.11
_exptl_crystal_size_min          0.06
_refine_diff_density_max         0.152
_refine_diff_density_min         -0.207
_refine_diff_density_rms         0.042
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_all   1.033
_refine_ls_goodness_of_fit_obs   1.077
_refine_ls_hydrogen_treatment    noref
_refine_ls_matrix_type           full
_refine_ls_number_parameters     135
_refine_ls_number_reflns         1456
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.039
_refine_ls_restrained_S_obs      1.077
_refine_ls_R_factor_all          0.0573
_refine_ls_R_factor_obs          0.0396
_refine_ls_shift/esd_max         0.013
_refine_ls_shift/esd_mean        0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0486P)^2^+1.2468P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.1012
_refine_ls_wR_factor_obs         0.0916
_reflns_number_observed          1144
_reflns_number_total             1461
_reflns_observed_criterion       >2sigma(I)
_cod_data_source_file            om990447k.cif
_cod_data_source_block           compound_3a
_cod_depositor_comments
;
The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc
w=1/[\s^2^(Fo^2^)+(0.0486P)^2^+1.2468P] 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^)+(0.0486P)^2^+1.2468P] where P=(Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_sg_symbol_H-M      C2/c
_cod_database_code               4077811