Exciton delocalization drives rapid singlet fission in nanoparticles of acene derivatives.
Pensack, Ryan D.; Tilley, Andrew J.; Parkin, Sean R.; Lee, Tia S.; Payne, Marcia M.; Gao, Dong; Jahnke, Ashlee A.; Oblinsky, Daniel G.; Li, Peng-Fei; Anthony, John E.; Seferos, Dwight S.; Scholes, Gregory D.; Journal of the American Chemical Society 137 (2015) 6790–6803; doi:10.1021/ja512668r

data_4123697
_publ_section_title
;
 Exciton delocalization drives rapid singlet fission in nanoparticles of
 acene derivatives.
;
_journal_issue                   21
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              6790
_journal_page_last               6803
_journal_paper_doi               10.1021/ja512668r
_journal_volume                  137
_journal_year                    2015
_chemical_formula_moiety         'C50 H66 Si2'
_chemical_formula_sum            'C50 H66 Si2'
_chemical_formula_weight         723.21
_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                78.673(2)
_cell_angle_beta                 84.728(2)
_cell_angle_gamma                84.507(2)
_cell_formula_units_Z            2
_cell_length_a                   5.8978(2)
_cell_length_b                   14.1866(4)
_cell_length_c                   26.4214(8)
_cell_measurement_reflns_used    8416
_cell_measurement_temperature    90.0(2)
_cell_measurement_theta_max      67.97
_cell_measurement_theta_min      3.32
_cell_volume                     2151.60(12)
_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, 2008)'
_computing_publication_material
; 
SHELX-97 (Sheldrick, 2008) and local procedures 
;
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      90.0(2)
_diffrn_detector_area_resol_mean 9.1
_diffrn_measured_fraction_theta_full 0.889
_diffrn_measured_fraction_theta_max 0.889
_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  0.0891
_diffrn_reflns_av_sigmaI/netI    0.1651
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -6
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       31
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            26424
_diffrn_reflns_theta_full        25.31
_diffrn_reflns_theta_max         25.31
_diffrn_reflns_theta_min         0.79
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.115
_exptl_absorpt_correction_T_max  0.999
_exptl_absorpt_correction_T_min  0.752
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'Scalepack (Otwinowski & Minor, 1997)'
_exptl_crystal_colour            blue
_exptl_crystal_density_diffrn    1.116
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       lath
_exptl_crystal_F_000             788
_exptl_crystal_size_max          0.35
_exptl_crystal_size_mid          0.02
_exptl_crystal_size_min          0.01
_refine_diff_density_max         0.459
_refine_diff_density_min         -0.408
_refine_diff_density_rms         0.098
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.131
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     545
_refine_ls_number_reflns         6958
_refine_ls_number_restraints     36
_refine_ls_restrained_S_all      1.128
_refine_ls_R_factor_all          0.1459
_refine_ls_R_factor_gt           0.0994
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0565P)^2^+14.8434P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2692
_refine_ls_wR_factor_ref         0.2894
_reflns_number_gt                4767
_reflns_number_total             6958
_reflns_threshold_expression     >2\s(I)
_cod_data_source_file            ja512668r_si_003.cif
_cod_data_source_block           x09103
_cod_depositor_comments
'Adding full bibliography for 4123696--4123698.cif.'
_cod_database_code               4123697