A persistent P,N-heterocyclic carbene.
Frey, Guido D; Song, Maoying; Bourg, Jean-Baptiste; Donnadieu, Bruno; Soleilhavoup, Michele; Bertrand, Guy; Chemical communications (Cambridge, England)  (2008) 4711–4713; doi:10.1039/b812333k

data_7103414
_publ_section_title
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 A persistent P,N-heterocyclic carbene.
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_journal_issue                   39
_journal_name_full               'Chemical communications (Cambridge, England)'
_journal_page_first              4711
_journal_page_last               4713
_journal_paper_doi               10.1039/b812333k
_journal_year                    2008
_chemical_formula_moiety         'C35 H54 N P'
_chemical_formula_sum            'C35 H54 N P'
_chemical_formula_weight         519.76
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 91.407(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   17.676(3)
_cell_length_b                   17.298(3)
_cell_length_c                   10.2989(16)
_cell_measurement_reflns_used    5040
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      25.65
_cell_measurement_theta_min      2.31
_cell_volume                     3148.1(9)
_computing_cell_refinement       'Bruker APEX2'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    Ortep3
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'Bruker Sir97'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega 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  0.0488
_diffrn_reflns_av_sigmaI/netI    0.0476
_diffrn_reflns_limit_h_max       20
_diffrn_reflns_limit_h_min       -20
_diffrn_reflns_limit_k_max       20
_diffrn_reflns_limit_k_min       -20
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            19438
_diffrn_reflns_theta_full        24.71
_diffrn_reflns_theta_max         24.71
_diffrn_reflns_theta_min         1.65
_exptl_absorpt_coefficient_mu    0.110
_exptl_absorpt_correction_T_max  0.9880
_exptl_absorpt_correction_T_min  0.9656
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   multi-scan
_exptl_crystal_colour            clear
_exptl_crystal_density_diffrn    1.097
_exptl_crystal_density_meas      0
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       'prism frag'
_exptl_crystal_F_000             1144
_exptl_crystal_size_max          0.32
_exptl_crystal_size_mid          0.13
_exptl_crystal_size_min          0.11
_refine_diff_density_max         0.653
_refine_diff_density_min         -0.354
_refine_diff_density_rms         0.056
_refine_ls_extinction_coef       0.0002(4)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.041
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     348
_refine_ls_number_reflns         5359
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.041
_refine_ls_R_factor_all          0.0710
_refine_ls_R_factor_gt           0.0501
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0741P)^2^+0.8112P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1207
_refine_ls_wR_factor_ref         0.1340
_reflns_number_gt                4058
_reflns_number_total             5359
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b812333k.txt
_cod_data_source_block           8c
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 
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_cod_original_sg_symbol_H-M      P2(1)/c
_cod_database_code               7103414