Mechanisms of Exchange Modulation in Trimethylenemethane-type Biradicals: The Roles of Conformation and Spin Density
David A. Shultz; Rosario M. Fico; Hyoyoung Lee; Jeff W. Kampf; Kristin Kirschbaum; A. Alan Pinkerton; Paul D. Boyle; Journal of the American Chemical Society 125 (2003) 15426–15432; doi:10.1021/ja037787o

data_4114493
_publ_contact_author
;
        David A. Shultz
    Department of Chemistry, 527 Dabney Hall
    North Carolina State University
    Raleigh, NC  27695-8204

;
_publ_contact_author_email       David_Shultz@ncsu.edu
_publ_contact_author_fax         (919)515-6972
_publ_contact_author_phone       (919)515-8920
_publ_section_title
;
 Mechanisms of Exchange Modulation in Trimethylenemethane-type Biradicals:
 The Roles of Conformation and Spin Density
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              15426
_journal_page_last               15432
_journal_paper_doi               10.1021/ja037787o
_journal_volume                  125
_journal_year                    2003
_chemical_formula_sum            'C31 H40 N2 O2'
_chemical_formula_weight         472.65
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                100.563(3)
_cell_angle_beta                 96.732(3)
_cell_angle_gamma                94.661(3)
_cell_formula_units_Z            2
_cell_length_a                   6.2971(5)
_cell_length_b                   11.9668(10)
_cell_length_c                   17.4475(12)
_cell_measurement_reflns_used    981
_cell_measurement_temperature    25(5)
_cell_measurement_theta_max      30
_cell_measurement_theta_min      3
_cell_volume                     1276.46(17)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      25(5)
_diffrn_measured_fraction_theta_full 0.314
_diffrn_measured_fraction_theta_max 0.314
_diffrn_measurement_device_type  Platform
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.1085
_diffrn_reflns_av_sigmaI/netI    0.0384
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -5
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -5
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            1314
_diffrn_reflns_theta_full        23.99
_diffrn_reflns_theta_max         23.99
_diffrn_reflns_theta_min         3.23
_exptl_absorpt_coefficient_mu    0.076
_exptl_crystal_colour            red
_exptl_crystal_density_diffrn    1.230
_exptl_crystal_description       'cracked plate'
_exptl_crystal_F_000             512
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.236
_refine_diff_density_min         -0.211
_refine_diff_density_rms         0.051
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.249
_refine_ls_hydrogen_treatment    'included with U(H)=1.5(1.2)*U(bonded C)'
_refine_ls_matrix_type           full
_refine_ls_number_parameters     161
_refine_ls_number_reflns         1254
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.249
_refine_ls_R_factor_all          0.1031
_refine_ls_R_factor_gt           0.0948
_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^)+(0.0970P)^2^+4.1112P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2259
_refine_ls_wR_factor_ref         0.2323
_reflns_number_gt                1129
_reflns_number_total             1254
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja037787orom20030722_093703.cif
_cod_data_source_block           abcd3a
_cod_database_code               4114493