Double-helix pattern in a model compound of non-linear optical polymers
Roberto Centore; Antonio Carella; Andrea Pugliese; Augusto Sirigu; Angela Tuzi; Acta Crystallographica Section C 62 (2006) o531–o533; doi:10.1107/S0108270106025108

data_2015487
_publ_section_title
;
 Double-helix pattern in a model compound of non-linear optical
 polymers
;
_journal_coeditor_code           GD3032
_journal_issue                   8
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              o531
_journal_page_last               o533
_journal_paper_doi               10.1107/S0108270106025108
_journal_volume                  62
_journal_year                    2006
_chemical_formula_iupac          'C18 H18 N4 O6'
_chemical_formula_moiety         'C18 H18 N4 O6'
_chemical_formula_sum            'C18 H18 N4 O6'
_chemical_formula_weight         386.36
_chemical_name_common            AZO33
_chemical_name_systematic
;
3,3'-[4-(4-nitrophenyldiazenyl)phenylimino]dipropionic acid
;
_space_group_IT_number           15
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-C 2yc'
_symmetry_space_group_name_H-M   'C 1 2/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL97
_cell_angle_alpha                90.00
_cell_angle_beta                 101.06(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   43.062(9)
_cell_length_b                   6.877(2)
_cell_length_c                   11.979(2)
_cell_measurement_reflns_used    211
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      20.451
_cell_measurement_theta_min      4.392
_cell_volume                     3481.5(14)
_computing_cell_refinement       'DIRAX/LSQ (Duisenberg <i>et al.</i>,  2000)'
_computing_data_collection       'COLLECT (Nonius, 2000)'
_computing_data_reduction        'EvalCCD (Duisenberg <i>et al.</i>,  2003)'
_computing_molecular_graphics
;
ORTEP3 for Windows (Farrugia, 1997) and
PLATON (Spek, 2003)
;
_computing_publication_material  'WinGX (Farrugia, 1999)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      173(2)
_diffrn_detector_area_resol_mean 9
_diffrn_measured_fraction_theta_full 0.991
_diffrn_measured_fraction_theta_max 0.991
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'Bruker Nonius KappaCCD area-detector'
_diffrn_measurement_method       'CCD rotation images, thick slices'
_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  0.0943
_diffrn_reflns_av_sigmaI/netI    0.1627
_diffrn_reflns_limit_h_max       53
_diffrn_reflns_limit_h_min       -49
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            10530
_diffrn_reflns_theta_full        26.50
_diffrn_reflns_theta_max         26.50
_diffrn_reflns_theta_min         1.93
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.113
_exptl_absorpt_correction_T_max  0.9977
_exptl_absorpt_correction_T_min  0.9363
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Bruker Nonius, 2002)'
_exptl_crystal_colour            red
_exptl_crystal_density_diffrn    1.474
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             1616
_exptl_crystal_size_max          0.59
_exptl_crystal_size_mid          0.13
_exptl_crystal_size_min          0.02
_refine_diff_density_max         0.408
_refine_diff_density_min         -0.317
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.001
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     253
_refine_ls_number_reflns         3584
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.001
_refine_ls_R_factor_all          0.1996
_refine_ls_R_factor_gt           0.0699
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.0577P)^2^+3.8477P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1254
_refine_ls_wR_factor_ref         0.1676
_reflns_number_gt                1587
_reflns_number_total             3584
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            gd3032.cif
_cod_data_source_block           I
_cod_original_sg_symbol_H-M      'C 2/c'
_cod_database_code               2015487
_cod_database_fobs_code          2015487