Hydrogen-bonded dihydrotetraazapentacenes.
He, Zikai; Liu, Danqing; Mao, Renxin; Tang, Qin; Miao, Qian; Organic letters 14 (2012) 1050–1053; doi:10.1021/ol203404q

data_1503603
_publ_section_title
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 Hydrogen-bonded dihydrotetraazapentacenes.
;
_journal_issue                   4
_journal_name_full               'Organic letters'
_journal_page_first              1050
_journal_page_last               1053
_journal_paper_doi               10.1021/ol203404q
_journal_volume                  14
_journal_year                    2012
_chemical_formula_sum            'C18 H12 N4'
_chemical_formula_weight         284.32
_chemical_melting_point          639.6(5)
_chemical_name_systematic
; 
 5,14-dihydro-1,4,5,14-tetraazapentacene 
;
_space_group_IT_number           62
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2ac 2n'
_symmetry_space_group_name_H-M   'P n m a'
_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                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   16.0215(15)
_cell_length_b                   11.2646(11)
_cell_length_c                   7.0956(7)
_cell_measurement_reflns_used    76
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      15
_cell_measurement_theta_min      15
_cell_volume                     1280.6(2)
_computing_cell_refinement       'BRUKER KAPPA APEXII DUO DIFFRACTOMETER'
_computing_data_collection       'BRUKER KAPPA APEXII DUO DIFFRACTOMETER'
_computing_data_reduction        'BRUKER KAPPA APEXII DUO DIFFRACTOMETER'
_computing_molecular_graphics    'SIEMENS SHELXTL'
_computing_publication_material  'SIEMENS SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.993
_diffrn_measurement_device_type  'BRUKER KAPPA APEXII DUO DIFFRACTOMETER'
_diffrn_measurement_method       'PHI & OMEGA SCAN'
_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  0.0699
_diffrn_reflns_av_sigmaI/netI    0.0597
_diffrn_reflns_limit_h_max       19
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       8
_diffrn_reflns_limit_l_min       -8
_diffrn_reflns_number            5215
_diffrn_reflns_theta_full        25.24
_diffrn_reflns_theta_max         25.24
_diffrn_reflns_theta_min         3.39
_exptl_absorpt_coefficient_mu    0.091
_exptl_absorpt_correction_T_max  0.7456
_exptl_absorpt_correction_T_min  0.5969
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.475
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             592
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.30
_exptl_crystal_size_min          0.20
_refine_diff_density_max         0.208
_refine_diff_density_min         -0.155
_refine_diff_density_rms         0.036
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.010
_refine_ls_hydrogen_treatment    riding
_refine_ls_matrix_type           full
_refine_ls_number_parameters     100
_refine_ls_number_reflns         1208
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.010
_refine_ls_R_factor_all          0.0691
_refine_ls_R_factor_gt           0.0444
_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^)+(0.0681P)^2^+0.1849P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1211
_refine_ls_wR_factor_ref         0.1424
_reflns_number_gt                773
_reflns_number_total             1208
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol203404q_si_002.cif
_cod_data_source_block           1,4,5,14-DHTAP
_cod_depositor_comments
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The following automatic conversions were performed:

'_chemical_melting_point' value '366-367 C' was changed to '639.6(5)'
- it was converted from degrees Celsius(C) to Kelvins(K), the average
value was taken and precision was
estimated.

'_symmetry_cell_setting' value 'Orthorhombic' changed to
'orthorhombic' according to
/home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary named
'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
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_cod_original_sg_symbol_H-M      Pnma
_cod_database_code               1503603