Isotactic N-Acrylamide Oligomers Assume self-assembled Sheet Structure: First Unequivocal Evidence From Crystal Structures
Sanjayan Gangadhar; R. G. Gonnade; Amol Kendhale; P. R. Rajamohanan; Chemical Communications  (2006) –; doi:10.1039/b601317a

data_7101243
_publ_section_title
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Isotactic N-Acrylamide Oligomers Assume self-assembled
Sheet Structure: First Unequivocal Evidence From Crystal Structures
;
_journal_issue                   26
_journal_name_full               'Chemical Communications'
_journal_paper_doi               10.1039/b601317a
_journal_year                    2006
_chemical_absolute_configuration syn
_chemical_formula_moiety         'C19 H36 N4 O4'
_chemical_formula_sum            'C19 H36 N4 O4'
_chemical_formula_weight         384.52
_chemical_name_common
;
4,6-Bis-methylcabamoyl-2,2,8,8-Tetramethyl carbamoyl-
nonanedioic acid bis-methylamide
;
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_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                   9.676(3)
_cell_length_b                   12.826(4)
_cell_length_c                   17.434(6)
_cell_measurement_reflns_used    1003
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      17.153
_cell_measurement_theta_min      2.335
_cell_volume                     2163.6(13)
_computing_cell_refinement       'BRUKER SMART'
_computing_data_collection       'BRUKER SMART'
_computing_data_reduction        'BRUKER SAINT'
_computing_molecular_graphics    SHELXTL
_computing_publication_material  SHELXTL
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device       'Bruker Smart APEX'
_diffrn_measurement_device_type  'CCD Area Detector'
_diffrn_measurement_method       'phi and 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  0.0710
_diffrn_reflns_av_sigmaI/netI    0.1235
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       20
_diffrn_reflns_limit_l_min       -20
_diffrn_reflns_number            10757
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         2.34
_exptl_absorpt_coefficient_mu    0.083
_exptl_absorpt_correction_T_max  0.9938
_exptl_absorpt_correction_T_min  0.9252
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'bruker sadabs'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.180
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       'Thin needle'
_exptl_crystal_F_000             840
_exptl_crystal_size_max          0.95
_exptl_crystal_size_mid          0.11
_exptl_crystal_size_min          0.08
_refine_diff_density_max         0.184
_refine_diff_density_min         -0.178
_refine_diff_density_rms         0.040
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.3(19)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.961
_refine_ls_hydrogen_treatment    riding
_refine_ls_matrix_type           full
_refine_ls_number_parameters     252
_refine_ls_number_reflns         3801
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.961
_refine_ls_R_factor_all          0.1227
_refine_ls_R_factor_gt           0.0574
_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^)+(0.0352P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1070
_refine_ls_wR_factor_ref         0.1240
_reflns_number_gt                2231
_reflns_number_total             3801
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b601317a.txt
_cod_depositor_comments
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The following automatic conversions were performed:
'_chemical_absolute_configuration' value 'SYN' changed to 'syn' according
to '/home/saulius/struct/CIF-dictionaries/cif_core.dic' dictionary named
'cif_core.dic' version 2.4.1 from 2010-06-29.

'_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_enum 1527 2010-12-29 10:47:43Z saulius 
;
_cod_original_sg_symbol_H-M      P2(1)2(1)2(1)
_cod_database_code               7101243