Pyrrole and polypyrrole-based liquid crystals containing azobenzene mesogenic groups
Chen, Yu; Harrison, William T. A.; Imrie, Corrie T.; Ryder, Karl S.; Journal of Materials Chemistry 12 (2002) 579–; doi:10.1039/b105976a

data_7204205
_publ_section_title
;
 Pyrrole and polypyrrole-based liquid crystals containing azobenzene
 mesogenic groups
;
_journal_issue                   3
_journal_name_full               'Journal of Materials Chemistry'
_journal_page_first              579
_journal_paper_doi               10.1039/b105976a
_journal_volume                  12
_journal_year                    2002
_chemical_formula_sum            'C19 H18 N4 O3'
_chemical_formula_weight         350.37
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_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                 111.696(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   11.8709(18)
_cell_length_b                   7.6449(12)
_cell_length_c                   20.891(4)
_cell_measurement_reflns_used    5770
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      27.80
_cell_measurement_theta_min      3.10
_cell_volume                     1761.6(5)
_computing_cell_refinement       'SMART (Bruker, 1999)'
_computing_data_collection       'SMART (Bruker, 1999)'
_computing_data_reduction        'SMART (Bruker, 1999)'
_computing_molecular_graphics    'ORTEP-3 (Farrugia, 1997)'
_computing_publication_material  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.922
_diffrn_measured_fraction_theta_max 0.922
_diffrn_measurement_device_type  'Bruker SMART CCD'
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  'silicon 111'
_diffrn_radiation_source         'Daresbury SRS station 9.8'
_diffrn_radiation_type           synchrotron
_diffrn_radiation_wavelength     0.69230
_diffrn_reflns_av_R_equivalents  0.0538
_diffrn_reflns_av_sigmaI/netI    0.0568
_diffrn_reflns_limit_h_max       16
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       28
_diffrn_reflns_limit_l_min       -29
_diffrn_reflns_number            16650
_diffrn_reflns_theta_full        29.21
_diffrn_reflns_theta_max         29.21
_diffrn_reflns_theta_min         1.80
_diffrn_standards_decay_%        0
_exptl_absorpt_coefficient_mu    0.092
_exptl_absorpt_correction_T_max  0.998
_exptl_absorpt_correction_T_min  0.922
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS (Bruker, 1999)'
_exptl_crystal_colour            orange
_exptl_crystal_density_diffrn    1.321
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       blade
_exptl_crystal_F_000             736
_exptl_crystal_size_max          0.90
_exptl_crystal_size_mid          0.12
_exptl_crystal_size_min          0.02
_refine_diff_density_max         0.257
_refine_diff_density_min         -0.267
_refine_diff_density_rms         0.054
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.88
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     356
_refine_ls_number_reflns         4764
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.88
_refine_ls_R_factor_all          0.117
_refine_ls_R_factor_gt           0.068
_refine_ls_shift/su_max          0.045
_refine_ls_shift/su_mean         0.004
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1296P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.180
_refine_ls_wR_factor_ref         0.198
_reflns_number_gt                2416
_reflns_number_total             4764
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            b105976a.txt
_cod_data_source_block           y639-3NO2
_cod_original_sg_symbol_H-M      P21/c
_cod_database_code               7204205