A Library of Selenourea Precursors to PbSe Nanocrystals with Size Distributions near the Homogeneous Limit.
Campos, Michael P.; Hendricks, Mark P.; Beecher, Alexander N.; Walravens, Willem; Swain, Robert A.; Cleveland, Gregory T.; Hens, Zeger; Sfeir, Matthew Y.; Owen, Jonathan S.; Journal of the American Chemical Society 139 (2017) 2296–2305; doi:10.1021/jacs.6b11021

data_4125574
_publ_section_title
;
 A Library of Selenourea Precursors to PbSe Nanocrystals with Size
 Distributions near the Homogeneous Limit.
;
_journal_issue                   6
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              2296
_journal_page_last               2305
_journal_paper_doi               10.1021/jacs.6b11021
_journal_volume                  139
_journal_year                    2017
_chemical_formula_sum            'C15 H30 N2 Se'
_chemical_formula_weight         317.37
_space_group_crystal_system      orthorhombic
_space_group_IT_number           33
_space_group_name_Hall           'P 2c -2n'
_space_group_name_H-M_alt        'P n a 21'
_symmetry_space_group_name_Hall  'P 2c -2n'
_symmetry_space_group_name_H-M   'P n a 21'
_atom_sites_solution_hydrogens   mixed
_audit_creation_method           SHELXL-2014
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   13.4556(14)
_cell_length_b                   20.0405(6)
_cell_length_c                   6.243(2)
_cell_measurement_reflns_used    9950
_cell_measurement_temperature    130(2)
_cell_measurement_theta_max      30.17
_cell_measurement_theta_min      2.53
_cell_volume                     1683.5(6)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-2014 (Sheldrick, 2014)'
_computing_structure_solution    'SHELXS-97 (Sheldrick 2008)'
_diffrn_ambient_temperature      130(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0447
_diffrn_reflns_av_unetI/netI     0.0396
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 0.999
_diffrn_reflns_limit_h_max       19
_diffrn_reflns_limit_h_min       -19
_diffrn_reflns_limit_k_max       28
_diffrn_reflns_limit_k_min       -28
_diffrn_reflns_limit_l_max       8
_diffrn_reflns_limit_l_min       -8
_diffrn_reflns_number            26325
_diffrn_reflns_point_group_measured_fraction_full 0.996
_diffrn_reflns_point_group_measured_fraction_max 0.996
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         30.530
_diffrn_reflns_theta_min         1.823
_exptl_absorpt_coefficient_mu    2.219
_exptl_absorpt_correction_T_max  0.7461
_exptl_absorpt_correction_T_min  0.2817
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.252
_exptl_crystal_description       block
_exptl_crystal_F_000             672
_exptl_crystal_size_max          1.170
_exptl_crystal_size_mid          0.730
_exptl_crystal_size_min          0.560
_refine_diff_density_max         0.933
_refine_diff_density_min         -0.383
_refine_diff_density_rms         0.056
_refine_ls_abs_structure_details
; 
 Flack x determined using 1814 quotients [(I+)-(I-)]/[(I+)+(I-)] 
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259). 
;
_refine_ls_abs_structure_Flack   0.025(5)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.028
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     198
_refine_ls_number_reflns         5113
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.028
_refine_ls_R_factor_all          0.0390
_refine_ls_R_factor_gt           0.0303
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0346P)^2^+0.0791P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0677
_refine_ls_wR_factor_ref         0.0702
_reflns_Friedel_coverage         0.837
_reflns_Friedel_fraction_full    0.992
_reflns_Friedel_fraction_max     0.991
_reflns_number_gt                4400
_reflns_number_total             5113
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            16.cif
_cod_data_source_block           campos5
_cod_depositor_comments
'Adding full bibliography for 4125565--4125579.cif.'
_cod_database_code               4125574
_shelx_estimated_absorpt_t_min   0.181
_shelx_estimated_absorpt_t_max   0.370
_shelxl_version_number           2014-3
_shelx_res_checksum              60957
_shelx_hkl_checksum              24383