Carbon's Three-Center, Four-Electron Tetrel Bond, Treated Experimentally.
Karim, Alavi; Schulz, Nils; Andersson, Hanna; Nekoueishahraki, Bijan; Carlsson, Anna-Carin C; Sarabi, Daniel; Valkonen, Arto; Rissanen, Kari; Gräfenstein, Jürgen; Keller, Sandro; Erdélyi, Máté; Journal of the American Chemical Society 140 (2018) 17571–17579; doi:10.1021/jacs.8b09367

data_4133305
_publ_section_title
;
 Carbon's Three-Center, Four-Electron Tetrel Bond, Treated Experimentally.
;
_journal_issue                   50
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              17571
_journal_page_last               17579
_journal_paper_doi               10.1021/jacs.8b09367
_journal_volume                  140
_journal_year                    2018
_chemical_formula_moiety         'C24 H20 N, B F4'
_chemical_formula_sum            'C24 H20 B F4 N'
_chemical_formula_weight         409.22
_space_group_crystal_system      monoclinic
_space_group_IT_number           15
_space_group_name_Hall           '-C 2yc'
_space_group_name_H-M_alt        'C 1 2/c 1'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2016/6
_cell_angle_alpha                90
_cell_angle_beta                 90.743(3)
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   25.7941(7)
_cell_length_b                   7.4589(2)
_cell_length_c                   20.1543(6)
_cell_measurement_reflns_used    6339
_cell_measurement_temperature    120(2)
_cell_measurement_theta_max      73.9430
_cell_measurement_theta_min      4.3720
_cell_volume                     3877.27(19)
_computing_cell_refinement       CrysAlisPro
_computing_data_collection       'CrysAlisPro 1.171.38.43 (Rigaku OD, 2015)'
_computing_data_reduction        CrysAlisPro
_computing_molecular_graphics    SHELXL-2016/6
_computing_publication_material  SHELXL-2016/6
_computing_structure_refinement  'SHELXL-2016/6 (Sheldrick, 2016)'
_computing_structure_solution    'SHELXT (Sheldrick, 2015)'
_diffrn_ambient_temperature      120(2)
_diffrn_detector_area_resol_mean 5.1977
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.976
_diffrn_measurement_device_type  'SuperNova, Dual, Cu at zero, Atlas'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_unetI/netI     0.0315
_diffrn_reflns_Laue_measured_fraction_full 0.997
_diffrn_reflns_Laue_measured_fraction_max 0.976
_diffrn_reflns_limit_h_max       32
_diffrn_reflns_limit_h_min       -32
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            3862
_diffrn_reflns_point_group_measured_fraction_full 0.997
_diffrn_reflns_point_group_measured_fraction_max 0.976
_diffrn_reflns_theta_full        67.684
_diffrn_reflns_theta_max         74.194
_diffrn_reflns_theta_min         3.427
_diffrn_source                   'micro-focus sealed X-ray tube'
_exptl_absorpt_coefficient_mu    0.903
_exptl_absorpt_correction_T_max  0.970
_exptl_absorpt_correction_T_min  0.870
_exptl_absorpt_correction_type   analytical
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.38.43 (Rigaku Oxford Diffraction, 2015)
Analytical numeric absorption correction using a multifaceted crystal
model based on expressions derived by R.C. Clark & J.S. Reid.
(Clark, R. C. & Reid, J. S. (1995). Acta Cryst. A51, 887-897)
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.402
_exptl_crystal_description       plate
_exptl_crystal_F_000             1696
_exptl_crystal_size_max          0.300
_exptl_crystal_size_mid          0.140
_exptl_crystal_size_min          0.040
_refine_diff_density_max         0.802
_refine_diff_density_min         -0.676
_refine_diff_density_rms         0.170
_refine_ls_extinction_coef       0.0014(3)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2016/6 (Sheldrick 2016)'
_refine_ls_goodness_of_fit_ref   1.140
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     273
_refine_ls_number_reflns         3862
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.140
_refine_ls_R_factor_all          0.1164
_refine_ls_R_factor_gt           0.1142
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.1329P)^2^+60.3878P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.3662
_refine_ls_wR_factor_ref         0.3671
_reflns_Friedel_coverage         0.000
_reflns_number_gt                3630
_reflns_number_total             3862
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja8b09367_si_002.cif
_cod_data_source_block           1-tritylpyridin-1-ium-BF4
_cod_original_sg_symbol_H-M      'C 2/c'
_cod_database_code               4133305
_shelx_shelxl_version_number     2016/6
_shelx_estimated_absorpt_t_min   0.773
_shelx_estimated_absorpt_t_max   0.965
_shelx_res_checksum              34613
_shelx_hkl_checksum              36212