Synthesis and characterization of electron-deficient pentacenes.
Swartz, Christopher R.; Parkin, Sean R.; Bullock, Joseph E.; Anthony, John E.; Mayer, Alex C.; Malliaras, George G.; Organic letters 7 (2005) 3163–3166; doi:10.1021/ol050872b

data_1506597
_publ_section_title
;
 Synthesis and characterization of electron-deficient pentacenes.
;
_journal_issue                   15
_journal_name_full               'Organic letters'
_journal_page_first              3163
_journal_page_last               3166
_journal_paper_doi               10.1021/ol050872b
_journal_volume                  7
_journal_year                    2005
_chemical_formula_moiety         'C44 H52 Br2 Si2'
_chemical_formula_sum            'C44 H52 Br2 Si2'
_chemical_formula_weight         796.86
_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                72.3531(10)
_cell_angle_beta                 83.9322(9)
_cell_angle_gamma                87.7702(9)
_cell_formula_units_Z            2
_cell_length_a                   9.1268(2)
_cell_length_b                   13.8290(3)
_cell_length_c                   16.6202(4)
_cell_measurement_reflns_used    110126
_cell_measurement_temperature    90.0(2)
_cell_measurement_theta_max      27.48
_cell_measurement_theta_min      1.00
_cell_volume                     1987.75(8)
_computing_cell_refinement       'SCALEPACK (Otwinowski & Minor, 1997)'
_computing_data_collection       'COLLECT (Nonius, 1998)'
_computing_data_reduction        'DENZO-SMN (Otwinowski & Minor, 1997)'
_computing_molecular_graphics    'XP in SHELXTL (Sheldrick, 1994)'
_computing_publication_material
; 
SHELX97-2 (Sheldrick, 1997) and local procedures 
;
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      90.0(2)
_diffrn_detector_area_resol_mean 18
_diffrn_measured_fraction_theta_full .998
_diffrn_measured_fraction_theta_max .998
_diffrn_measurement_device_type  'Nonius KappaCCD diffractometer'
_diffrn_measurement_method       '\w scans at fixed \c = 55\%'
_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  0.0940
_diffrn_reflns_av_sigmaI/netI    0.0703
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            9092
_diffrn_reflns_theta_full        27.49
_diffrn_reflns_theta_max         27.49
_diffrn_reflns_theta_min         1.55
_exptl_absorpt_coefficient_mu    2.129
_exptl_absorpt_correction_T_max  0.7407
_exptl_absorpt_correction_T_min  0.6755
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'Scalepack (Otwinowski & Minor, 1997)'
_exptl_crystal_colour            'dark blue'
_exptl_crystal_density_diffrn    1.331
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       'irregular block'
_exptl_crystal_F_000             828
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.15
_refine_diff_density_max         .763
_refine_diff_density_min         -.983
_refine_diff_density_rms         .102
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.021
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     445
_refine_ls_number_reflns         9092
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.021
_refine_ls_R_factor_all          0.0842
_refine_ls_R_factor_gt           0.0490
_refine_ls_shift/su_max          0.003
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0634P)^2^+1.5087P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1126
_refine_ls_wR_factor_ref         0.1268
_reflns_number_gt                6422
_reflns_number_total             9092
_reflns_threshold_expression     >2\s(I)
_cod_data_source_file            ol050872bsi20050609_051818.cif
_cod_data_source_block           k04234x
_cod_database_code               1506597