Quinones as Electron Acceptors. X-Ray Structures, Spectral (EPR, UV-vis) Characteristics and Electron-Transfer Reactivities of Their Reduced Anion Radicals as Separated vs Contact Ion Pairs
Jian-Ming Lü; Sergiy V. Rosokha; Ivan S. Neretin; Jay K. Kochi; Journal of the American Chemical Society 128 (2006) 16708–16719; doi:10.1021/ja066471o

data_4111285
_publ_section_title
;
 Quinones as Electron Acceptors. X-Ray Structures, Spectral (EPR, UV-vis)
 Characteristics and Electron-Transfer Reactivities of Their Reduced Anion
 Radicals as Separated vs Contact Ion Pairs
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              16708
_journal_page_last               16719
_journal_paper_doi               10.1021/ja066471o
_journal_volume                  128
_journal_year                    2006
_chemical_formula_moiety         'C26 H28 K O8'
_chemical_formula_sum            'C26 H28 K O8'
_chemical_formula_weight         507.58
_chemical_name_common            '[DBCrown K]+ BQ-'
_chemical_name_systematic
; 
 Dibenzo-18-crown-6 potassium benzoquinonide
;
_space_group_IT_number           144
_symmetry_cell_setting           hexagonal
_symmetry_space_group_name_Hall  'P 31'
_symmetry_space_group_name_H-M   'P 31'
_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                 90.00
_cell_angle_gamma                120.00
_cell_formula_units_Z            3
_cell_length_a                   15.283(3)
_cell_length_b                   15.283(3)
_cell_length_c                   9.112(3)
_cell_measurement_reflns_used    22
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      13.81
_cell_measurement_theta_min      2.67
_cell_volume                     1843.2(8)
_computing_cell_refinement       'SAINT V6.28 (BrukerAXS, 1997-2001)'
_computing_data_collection       'SMART V5.630 (BrukerAXS, 1997-2001)'
_computing_data_reduction        'SAINT & SADABS V2.06 (Sheldrick, 2000)'
_computing_molecular_graphics    'XP V5.06 (BrukerAXS, 1997-99)'
_computing_publication_material  'SHELXL-93, XCIF V5.05 (BrukerAXS, 1997-99)'
_computing_structure_refinement  'SHELXTL v. 6.12 (Sheldrick, 2001)'
_computing_structure_solution    'SHELXTL v. 6.12 (Sheldrick, 2001)'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device       'Siemens SMART'
_diffrn_measurement_method
;
\w-scan, frame range 0.3 deg, hemisphere
;
_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  0.0999
_diffrn_reflns_av_sigmaI/netI    0.1446
_diffrn_reflns_limit_h_max       20
_diffrn_reflns_limit_h_min       -19
_diffrn_reflns_limit_k_max       20
_diffrn_reflns_limit_k_min       -20
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -5
_diffrn_reflns_number            12792
_diffrn_reflns_theta_full        28.05
_diffrn_reflns_theta_max         28.05
_diffrn_reflns_theta_min         1.54
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 0
_diffrn_standards_interval_time  0
_diffrn_standards_number         none
_exptl_absorpt_coefficient_mu    0.265
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.372
_exptl_crystal_description       needle
_exptl_crystal_F_000             801
_exptl_crystal_size_max          0.4
_exptl_crystal_size_mid          0.1
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.163
_refine_diff_density_min         -0.134
_refine_diff_density_rms         0.035
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.07(5)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.804
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     316
_refine_ls_number_reflns         4079
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      0.804
_refine_ls_R_factor_all          0.1138
_refine_ls_R_factor_gt           0.0386
_refine_ls_shift/su_max          0.006
_refine_ls_shift/su_mean         0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
; calc 
 [0.00000+1.00000exp(1.50(sin\q/\l)^2^)]/ 
   [\s^2^(Fo^2^)+0.0000+0.0000*P+(0.0150P)^2^+0.0000sin\q/\l] 
 where P = 0.33333Fo^2^ + 0.66667Fc^2^ 
;
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0644
_refine_ls_wR_factor_ref         0.0774
_reflns_number_gt                1705
_reflns_number_total             4079
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja066471osi20060907_103922.cif
_cod_data_source_block           lu3
_cod_original_cell_volume        1843.3(8)
_cod_database_code               4111285