Computational prediction and experimental verification of pyridine-based helical oligoamides containing four repeating units per helical turn
'Wei Qiang Ong; Huaiqing Zhao; Zhiyun Du; Jared Ze Yang Yeh; Changliang Ren; Leon Zhen Wei Tan; Kun Zhang; Huaqiang Zeng; Chem.Commun. 47 (2011) 6416–; doi:10.1039/c1cc11532d

data_7106461
_publ_section_title
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 Computational prediction and experimental verification of pyridine-based
 helical oligoamides containing four repeating units per helical turn
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_journal_name_full               Chem.Commun.
_journal_page_first              6416
_journal_paper_doi               10.1039/c1cc11532d
_journal_volume                  47
_journal_year                    2011
_chemical_formula_sum            'C20 H16 N4 O4'
_chemical_formula_weight         376.37
_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           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.6040(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   34.441(2)
_cell_length_b                   5.2810(3)
_cell_length_c                   19.1556(12)
_cell_measurement_reflns_used    2434
_cell_measurement_temperature    223(2)
_cell_measurement_theta_max      27.40
_cell_measurement_theta_min      2.42
_cell_volume                     3483.9(4)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      223(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
_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  0.0331
_diffrn_reflns_av_sigmaI/netI    0.0395
_diffrn_reflns_limit_h_max       42
_diffrn_reflns_limit_h_min       -44
_diffrn_reflns_limit_k_max       6
_diffrn_reflns_limit_k_min       -6
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -24
_diffrn_reflns_number            11784
_diffrn_reflns_theta_full        27.48
_diffrn_reflns_theta_max         27.48
_diffrn_reflns_theta_min         2.13
_exptl_absorpt_coefficient_mu    0.103
_exptl_absorpt_correction_T_max  0.9918
_exptl_absorpt_correction_T_min  0.9314
_exptl_absorpt_correction_type   'Sadabs, (Sheldrick 2001)'
_exptl_crystal_colour            COLOURLESS
_exptl_crystal_density_diffrn    1.435
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       ROD
_exptl_crystal_F_000             1568
_exptl_crystal_size_max          0.70
_exptl_crystal_size_mid          0.10
_exptl_crystal_size_min          0.08
_refine_diff_density_max         0.215
_refine_diff_density_min         -0.212
_refine_diff_density_rms         0.040
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.041
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     262
_refine_ls_number_reflns         3989
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.041
_refine_ls_R_factor_all          0.0614
_refine_ls_R_factor_gt           0.0469
_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^)+(0.0446P)^2^+1.8224P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1086
_refine_ls_wR_factor_ref         0.1154
_reflns_number_gt                3139
_reflns_number_total             3989
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c1cc11532d.txt
_cod_data_source_block           8185
_cod_depositor_comments
;
The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'Not Measused' was changed to '?'
- the value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 
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_cod_original_sg_symbol_H-M      C2/c
_cod_database_code               7106461