A stable heavier group 14 analogue of vinylidene
Arnab Rit; Jesus Campos; Haoyu Niu; Simon Aldridge; Nature Chemistry 8 (2016) 1022–1026; doi:10.1038/nchem.2597

data_1552003
_publ_section_title
;
 A stable heavier group 14 analogue of vinylidene
;
_journal_name_full               'Nature Chemistry'
_journal_page_first              1022
_journal_page_last               1026
_journal_paper_doi               10.1038/nchem.2597
_journal_volume                  8
_journal_year                    2016
_chemical_formula_sum            'C63 H92 B2 Ge2 N6'
_chemical_formula_weight         1100.22
_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
_cell_angle_alpha                90
_cell_angle_beta                 101.731(3)
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   51.304(2)
_cell_length_b                   13.7692(6)
_cell_length_c                   27.1756(5)
_cell_measurement_reflns_used    2863
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      77.0018
_cell_measurement_theta_min      3.6435
_cell_volume                     18796.3(12)
_computing_cell_refinement       'CrysAlisPro, (Agilent, 2011)'
_computing_data_collection       'SuperNova, (Oxford Diffraction, 2010)'
_computing_data_reduction        'CrysAlisPro, (Agilent, 2011)'
_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_computing_structure_solution    'SHELXT 2014/5 (Sheldrick, 2014)'
_diffrn_ambient_temperature      150(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.968
_diffrn_measurement_device       Area
_diffrn_measurement_device_type  'Oxford Diffraction SuperNova'
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           'Cu K\a'
_diffrn_radiation_wavelength     1.54180
_diffrn_reflns_av_R_equivalents  0.0737
_diffrn_reflns_av_unetI/netI     0.0696
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.968
_diffrn_reflns_limit_h_max       63
_diffrn_reflns_limit_h_min       -64
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       34
_diffrn_reflns_limit_l_min       -33
_diffrn_reflns_number            77510
_diffrn_reflns_point_group_measured_fraction_full 0.999
_diffrn_reflns_point_group_measured_fraction_max 0.968
_diffrn_reflns_theta_full        67.684
_diffrn_reflns_theta_max         78.397
_diffrn_reflns_theta_min         3.322
_exptl_absorpt_coefficient_mu    0.988
_exptl_absorpt_correction_T_max  1.0000
_exptl_absorpt_correction_T_min  0.7845
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'CrysAlisPro, (Agilent, 2011)'
_exptl_crystal_colour            red
_exptl_crystal_density_diffrn    0.778
_exptl_crystal_density_meas      .
_exptl_crystal_density_method    .
_exptl_crystal_description       prism
_exptl_crystal_F_000             4688
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.16
_exptl_crystal_size_min          0.10
_platon_squeeze_details
;
The unit cell contains 4 molecules of the Ge dimer 
[C63 H92 B2 Ge2 N6] which have been treated as a diffuse
contribution to the overall scattering without specific atom 
positions by SQUEEZE/PLATON. The reason to adopt this drastic
decision comes from the fact that these four molecules, although
identifiable by the Fourier electron density map, were too highly
disordered. More precisely, the 'whole molecule' was disordered over
 at least two positions. This adds to the fact that the whole 
molecule was additionally disordered over  the c plane. Modeling
 this proved to be extremely difficult and refinement often became
 unstable. Given the fact that there are other eight well-behaved
 molecules of the same species we decided to squeeze the disordered
 part. 
;
_refine_diff_density_max         0.765
_refine_diff_density_min         -1.301
_refine_diff_density_rms         0.083
_refine_ls_extinction_coef       .
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.120
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     680
_refine_ls_number_reflns         19571
_refine_ls_number_restraints     13
_refine_ls_restrained_S_all      1.121
_refine_ls_R_factor_all          0.1066
_refine_ls_R_factor_gt           0.0793
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0982P)^2^+48.2144P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2115
_refine_ls_wR_factor_ref         0.2418
_reflns_Friedel_coverage         0.000
_reflns_Friedel_fraction_full    .
_reflns_Friedel_fraction_max     .
_reflns_number_gt                13324
_reflns_number_total             19571
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            nchem.2597-s4.cif
_cod_data_source_block           376ARRT15_jc
_cod_original_cell_volume        18796.2(12)
_cod_original_sg_symbol_H-M      'C 2/c'
_cod_database_code               1552003
_platon_squeeze_void_probe_radius 1.20