Conformationally Constrained, Stable, Triplet Ground State (S=1) Nitroxide Diradicals. Antiferromagnetic Chains of S=1 Diradicals
Andrzej Rajca; Masahiro Takahashi; Maren Pink; Gaëlle Spagnol; Suchada Rajca; Journal of the American Chemical Society 129 (2007) 10159–10170; doi:10.1021/ja0712017

data_4109780
_publ_section_title
;
 Conformationally Constrained, Stable, Triplet Ground State (S=1)
 Nitroxide Diradicals. Antiferromagnetic Chains of S=1 Diradicals
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              10159
_journal_page_last               10170
_journal_paper_doi               10.1021/ja0712017
_journal_volume                  129
_journal_year                    2007
_chemical_formula_moiety         'C28 H38 N2 O4'
_chemical_formula_sum            'C28 H38 N2 O4'
_chemical_formula_weight         466.60
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           61
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2ac 2ab'
_symmetry_space_group_name_H-M   'P b c a'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   riding
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   8.658(5)
_cell_length_b                   20.436(11)
_cell_length_c                   28.965(17)
_cell_measurement_reflns_used    1496
_cell_measurement_temperature    95(2)
_cell_measurement_theta_max      12.9
_cell_measurement_theta_min      2.2
_cell_volume                     5125(5)
_computing_cell_refinement       'SAINT (Bruker, 2003)'
_computing_data_collection       'SMART (Bruker, 2001)'
_computing_data_reduction        'SAINT (Bruker, 2003)'
_computing_molecular_graphics    'SHELXTL (Bruker, 2003), XTEL (loc. libr.)'
_computing_publication_material  'SHELXTL (Bruker, 2003)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SIR-2004 (Burla et al., 2005)'
_diffrn_ambient_temperature      95(2)
_diffrn_detector                 'CCD area detector'
_diffrn_detector_area_resol_mean 44.52
_diffrn_detector_type            'Bruker SMART 6000'
_diffrn_measured_fraction_theta_full 0.985
_diffrn_measured_fraction_theta_max 0.985
_diffrn_measurement_details
'0.5 degree frames measured for 2 seconds each'
_diffrn_measurement_device       'three-circle goniometer with fixed chi'
_diffrn_measurement_device_type  'Bruker Platform goniometer'
_diffrn_measurement_method       'omega and phi scans'
_diffrn_radiation_monochromator  'diamond 1 1 1'
_diffrn_radiation_source         synchrotron
_diffrn_radiation_type           synchrotron
_diffrn_radiation_wavelength     0.43321
_diffrn_reflns_av_R_equivalents  0.3536
_diffrn_reflns_av_sigmaI/netI    0.2256
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       24
_diffrn_reflns_limit_k_min       -22
_diffrn_reflns_limit_l_max       34
_diffrn_reflns_limit_l_min       -34
_diffrn_reflns_number            25457
_diffrn_reflns_theta_full        15.07
_diffrn_reflns_theta_max         15.07
_diffrn_reflns_theta_min         0.86
_exptl_absorpt_coefficient_mu    0.051
_exptl_absorpt_correction_T_max  0.9995
_exptl_absorpt_correction_T_min  0.9954
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS, R. Blessing; 1995'
_exptl_crystal_colour            red
_exptl_crystal_density_diffrn    1.209
_exptl_crystal_description       'flat needle'
_exptl_crystal_F_000             2016
_exptl_crystal_size_max          0.09
_exptl_crystal_size_mid          0.03
_exptl_crystal_size_min          0.01
_refine_diff_density_max         0.928
_refine_diff_density_min         -0.389
_refine_diff_density_rms         0.129
_refine_ls_extinction_coef       0.094(13)
_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   0.993
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     347
_refine_ls_number_reflns         4586
_refine_ls_number_restraints     72
_refine_ls_restrained_S_all      0.988
_refine_ls_R_factor_all          0.1937
_refine_ls_R_factor_gt           0.1178
_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^)+(0.1753P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2739
_refine_ls_wR_factor_ref         0.3285
_reflns_number_gt                2238
_reflns_number_total             4586
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja0712017si20070219_032027.cif
_cod_data_source_block           cmc0573
_cod_database_code               4109780