Combination vs. disproportionation in dialkyl biradicals. Selectivity reversal in a crystalline solid.
Choe, Tina; Khan, Saeed I.; Garcia-Garibay, Miguel A; Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology 5 (2006) 449–451; doi:10.1039/b603909j

data_1516187
_publ_section_title
;
 Combination vs. disproportionation in dialkyl biradicals. Selectivity
 reversal in a crystalline solid.
;
_journal_issue                   5
_journal_name_full
'Photochemical &amp; photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology'
_journal_page_first              449
_journal_page_last               451
_journal_paper_doi               10.1039/b603909j
_journal_volume                  5
_journal_year                    2006
_chemical_formula_moiety         'C22 H22 O4'
_chemical_formula_sum            'C22 H22 O4'
_chemical_formula_weight         350.40
_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                 90.134(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   14.8162(12)
_cell_length_b                   14.8987(12)
_cell_length_c                   8.3482(7)
_cell_measurement_reflns_used    2649
_cell_measurement_temperature    298(2)
_cell_measurement_theta_max      22.35
_cell_measurement_theta_min      2.73
_cell_volume                     1842.8(3)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      298(2)
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.972
_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  0.0477
_diffrn_reflns_av_sigmaI/netI    0.0625
_diffrn_reflns_limit_h_max       19
_diffrn_reflns_limit_h_min       -19
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       -19
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       -10
_diffrn_reflns_number            16259
_diffrn_reflns_theta_full        27.00
_diffrn_reflns_theta_max         28.30
_diffrn_reflns_theta_min         1.94
_exptl_absorpt_coefficient_mu    0.086
_exptl_absorpt_correction_T_max  0.9872
_exptl_absorpt_correction_T_min  0.9415
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'Sadabs (Bruker)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.263
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       tablet
_exptl_crystal_F_000             744
_exptl_crystal_size_max          0.35
_exptl_crystal_size_mid          0.25
_exptl_crystal_size_min          0.15
_refine_diff_density_max         0.266
_refine_diff_density_min         -0.145
_refine_diff_density_rms         0.032
_refine_ls_extinction_coef       0.0051(14)
_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   0.992
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     238
_refine_ls_number_reflns         4455
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.992
_refine_ls_R_factor_all          0.1383
_refine_ls_R_factor_gt           0.0521
_refine_ls_shift/su_max          0.004
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0693P)^2^+0.0980P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1212
_refine_ls_wR_factor_ref         0.1538
_reflns_number_gt                2043
_reflns_number_total             4455
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b603909j.txt
_cod_data_source_block           3
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to
/usr/data/users/saulius/automatic-downloads/retrospective/RSC/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 2281 2013-09-26 08:29:07Z andrius 
;
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               1516187