Dispersion Forces and Counterintuitive Steric Effects in Main Group Molecules: Heavier Group 14 (Si-Pb) Dichalcogenolate Carbene Analogues with Sub-90° Interligand Bond Angles
Brian D. Rekken; Thomas M. Brown; James C. Fettinger; Felicitas Lips; Heikki M. Tuononen; Rolfe H. Herber; Philip P. Power; Journal of the American Chemical Society 135 (2013) 10134–10148; doi:10.1021/ja403802a

data_4120072
_publ_section_title
;
 Dispersion Forces and Counterintuitive Steric Effects in Main Group
 Molecules: Heavier Group 14 (Si-Pb) Dichalcogenolate Carbene Analogues
 with Sub-90\% Interligand Bond Angles
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              10134
_journal_page_last               10148
_journal_paper_doi               10.1021/ja403802a
_journal_volume                  135
_journal_year                    2013
_chemical_formula_moiety         'C60 H74 Ge Se2'
_chemical_formula_sum            'C60 H74 Ge Se2'
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_space_group_IT_number           61
_space_group_name_Hall           '-P 2ac 2ab'
_space_group_name_H-M_alt        'P b c a'
_symmetry_space_group_name_Hall  '-P 2ac 2ab'
_symmetry_space_group_name_H-M   'P b c a'
_atom_sites_solution_hydrogens   geom
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_cell_angle_beta                 90
_cell_angle_gamma                90
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_cell_length_b                   16.3476(15)
_cell_length_c                   34.614(3)
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_cell_measurement_theta_min      2.42
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_computing_cell_refinement       'SAINT (8.27b) (Bruker, 2012)'
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_diffrn_ambient_temperature      90(2)
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_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
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_diffrn_reflns_limit_l_min       -44
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_diffrn_reflns_point_group_measured_fraction_full 1.000
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_refine_ls_extinction_coef       0.00016(3)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
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_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
;
 w=1/[\s^2^(Fo^2^)+(0.0295P)^2^+8.8440P]
 where P=(Fo^2^+2Fc^2^)/3
;
_refine_ls_weighting_scheme      calc
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_reflns_number_gt                10502
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_cod_database_code               4120072
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_shelx_res_checksum              43369