"Tschitschibabin type biradicals": benzenoid or quinoid?
Ravat, Prince; Baumgarten, Martin; Physical chemistry chemical physics : PCCP 17 (2015) 983–991; doi:10.1039/c4cp03522d

data_7218748
_publ_section_title
;
 &quot;Tschitschibabin type biradicals&quot;: benzenoid or quinoid?
;
_journal_issue                   2
_journal_name_full               'Physical chemistry chemical physics : PCCP'
_journal_page_first              983
_journal_page_last               991
_journal_paper_doi               10.1039/c4cp03522d
_journal_volume                  17
_journal_year                    2015
_chemical_formula_moiety         'C26 H30 N2 O2'
_chemical_formula_sum            'C26 H30 N2 O2'
_chemical_formula_weight         402.54
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yab'
_symmetry_space_group_name_H-M   'P 1 21/a 1'
_atom_sites_solution_hydrogens   difmap
_atom_sites_solution_primary     direct
_audit_creation_date             14-02-12
_audit_creation_method           CRYSTALS_ver_14.40
_cell_angle_alpha                90
_cell_angle_beta                 94.802(2)
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   8.8404(2)
_cell_length_b                   8.9886(3)
_cell_length_c                   13.3460(4)
_cell_measurement_reflns_used    0
_cell_measurement_temperature    120
_cell_measurement_theta_max      0
_cell_measurement_theta_min      0
_cell_volume                     1056.79(5)
_computing_cell_refinement       'DENZO/SCALEPACK (Otwinowski & Minor, 1997)'
_computing_data_collection       'COLLECT (Nonius, 2001).'
_computing_data_reduction        'DENZO/SCALEPACK (Otwinowski & Minor, 1997)'
_computing_molecular_graphics    'CAMERON (Watkin et al., 1996)'
_computing_publication_material  'CRYSTALS (Betteridge et al., 2003)'
_computing_structure_refinement  'CRYSTALS (Betteridge et al., 2003)'
_computing_structure_solution    'SHELXS 86 (Sheldrick, 1986)'
_diffrn_ambient_temperature      120
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device       Area
_diffrn_measurement_device_type  'Nonius KappaCCD'
_diffrn_measurement_method       '\f & \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.055
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            13179
_diffrn_reflns_theta_full        30.038
_diffrn_reflns_theta_max         30.038
_diffrn_reflns_theta_min         3.499
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.080
_exptl_absorpt_correction_T_max  0.99
_exptl_absorpt_correction_T_min  0.96
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'DENZO/SCALEPACK (Otwinowski & Minor, 1997)'
_exptl_crystal_colour            'dark red'
_exptl_crystal_density_diffrn    1.265
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             432
_exptl_crystal_size_max          0.420
_exptl_crystal_size_mid          0.290
_exptl_crystal_size_min          0.090
_refine_diff_density_max         0.31
_refine_diff_density_min         -0.33
_refine_ls_extinction_method     None
_refine_ls_goodness_of_fit_ref   1.0718
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     136
_refine_ls_number_reflns         2304
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.0659
_refine_ls_R_factor_gt           0.0505
_refine_ls_shift/su_max          0.0016420
_refine_ls_shift/su_mean         0.0004057
_refine_ls_structure_factor_coef F
_refine_ls_weighting_details
;
 Method, part 1, Chebychev polynomial, (Watkin, 1994, Prince, 1982) 
 [weight] = 1.0/[A~0~*T~0~(x)+A~1~*T~1~(x) ... +A~n-1~]*T~n-1~(x)] 
 where A~i~ are the Chebychev coefficients listed below and x= Fcalc/Fmax 
 Method = Robust Weighting (Prince, 1982) 
 W = [weight] * [1-(deltaF/6*sigmaF)^2^]^2^ 
 A~i~ are: 
 1.40 0.609 0.891 
;
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.0643
_refine_ls_wR_factor_gt          0.0579
_refine_ls_wR_factor_ref         0.0574
_reflns_limit_h_max              12
_reflns_limit_h_min              -12
_reflns_limit_k_max              12
_reflns_limit_k_min              0
_reflns_limit_l_max              18
_reflns_limit_l_min              0
_reflns_number_gt                2464
_reflns_number_total             3090
_reflns_threshold_expression     I>2.0\s(I)
_cod_data_source_file            c4cp03522d2.cif
_cod_data_source_block           ravterp_120
_cod_depositor_comments
'Adding full bibliography for 7218748--7218750.cif.'
_cod_original_sg_symbol_H-M      'P 1 21/a 1 '
_cod_database_code               7218748
_iucr_refine_instruction_details_constraints
;
BLOCK SCALE X'S, U'S 
RIDE C   (   5,X'S) H   (  51,X'S) 
RIDE C   (   2,X'S) H   (  21,X'S) 
RIDE C   (   9,X'S) H   (  91,X'S) 
RIDE C   (   1,X'S) H   (  11,X'S) 
RIDE C   (   6,X'S) H   (  61,X'S) 
RIDE C   (   8,X'S) H   (  81,X'S) 
RIDE C   (  11,X'S) H   ( 111,X'S) H   ( 112,X'S) H   ( 113,X'S) 
RIDE C   (  12,X'S) H   ( 121,X'S) H   ( 122,X'S) H   ( 123,X'S) 
RIDE C   (  13,X'S) H   ( 131,X'S) H   ( 132,X'S) H   ( 133,X'S) 
END                                                                             
;
_iucr_refine_instruction_details_restraints
;
NO 
REM   HREST   START (DO NOT REMOVE THIS LINE) 
REM   HREST   END (DO NOT REMOVE THIS LINE) 
END                                                                             
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