Stabilized and Persistent Allenylketenes
Wenwei Huang; Decai Fang; Karen Temple; Thomas T. Tidwell; Journal of the American Chemical Society 119 (1997) 2832–2838; doi:10.1021/ja963496m

data_4116940
_publ_section_title
;
 Stabilized and Persistent Allenylketenes
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              2832
_journal_page_last               2838
_journal_paper_doi               10.1021/ja963496m
_journal_volume                  119
_journal_year                    1997
_chemical_formula_sum            'C17 H24 O Si2'
_chemical_formula_weight         300.54
_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                 96.011(13)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   26.625(5)
_cell_length_b                   6.1358(10)
_cell_length_c                   22.047(3)
_cell_measurement_reflns_used    42
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      11.97
_cell_measurement_theta_min      4.80
_cell_volume                     3581.9(10)
_computing_cell_refinement       'Siemens XSCANS'
_computing_data_collection       'Siemens XSCANS'
_computing_data_reduction        'Siemens SHELXTL'
_computing_molecular_graphics    'Siemens SHELXTL'
_computing_publication_material  'Siemens SHELXTL'
_computing_structure_refinement  'SHELXL-93 (Sheldrick, 1993)'
_computing_structure_solution    'SHELXS-86 (Sheldrick, 1990)'
_diffrn_ambient_temperature      173(2)
_diffrn_measurement_device       'Siemens P4'
_diffrn_measurement_method       '\w scans'
_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  0.0326
_diffrn_reflns_av_sigmaI/netI    0.0465
_diffrn_reflns_limit_h_max       34
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       28
_diffrn_reflns_limit_l_min       -28
_diffrn_reflns_number            3981
_diffrn_reflns_theta_max         26.99
_diffrn_reflns_theta_min         2.53
_diffrn_standards_decay_%        10.41
_diffrn_standards_interval_count 97
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.193
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.115
_exptl_crystal_density_meas      ?
_exptl_crystal_description       prism
_exptl_crystal_F_000             1296
_exptl_crystal_size_max          0.58
_exptl_crystal_size_mid          0.57
_exptl_crystal_size_min          0.45
_refine_diff_density_max         0.385
_refine_diff_density_min         -0.238
_refine_diff_density_rms         0.049
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_all   0.925
_refine_ls_goodness_of_fit_obs   1.015
_refine_ls_hydrogen_treatment    'riding atoms'
_refine_ls_matrix_type           full
_refine_ls_number_parameters     187
_refine_ls_number_reflns         3900
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.925
_refine_ls_restrained_S_obs      1.015
_refine_ls_R_factor_all          0.0508
_refine_ls_R_factor_obs          0.0370
_refine_ls_shift/esd_max         -0.001
_refine_ls_shift/esd_mean        0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0602P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.0983
_refine_ls_wR_factor_obs         0.0937
_reflns_number_observed          2982
_reflns_number_total             3900
_reflns_observed_criterion       >2sigma(I)
_cod_data_source_file            ja963496m.cif
_cod_data_source_block           s9618
_cod_depositor_comments
;
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^)+(0.0602P)^2^+0.0000P] 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^)+(0.0602P)^2^+0.0000P] 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        3581.8(11)
_cod_database_code               4116940