Comparative Structural Studies on Homologues of Amides and Reverse Amides: Unprecedented 4-fold Interpenetrated Quartz Network, New β-Sheet, and Two-Dimensional Layers
Rajput, Lalit; Singha, Subhankar; Biradha, Kumar; Crystal Growth & Design 7 (2007) 2788–; doi:10.1021/cg0706417

data_4504458
_publ_section_title
;
 Comparative Structural Studies on Homologues of Amides and Reverse
 Amides: Unprecedented 4-fold Interpenetrated Quartz Network, New
 \b-Sheet, and Two-Dimensional Layers
;
_journal_issue                   12
_journal_name_full               'Crystal Growth &amp; Design'
_journal_page_first              2788
_journal_paper_doi               10.1021/cg0706417
_journal_volume                  7
_journal_year                    2007
_chemical_formula_sum            'C16 H18 N4 O2'
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_atom_sites_solution_secondary   difmap
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_cell_angle_beta                 90.00
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_cell_length_c                   17.727(4)
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_computing_cell_refinement       CAD4
_computing_data_collection       CAD4
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_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
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_diffrn_measurement_method       \w-scan
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_exptl_absorpt_coefficient_mu    0.089
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_exptl_crystal_density_diffrn    1.300
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_exptl_crystal_description       diamonds
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_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
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_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0908P)^2^+0.0033P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
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_reflns_number_gt                535
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_cod_data_source_file            cg0706417-file002.cif
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_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Trigonal' changed to 'trigonal'
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 

The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'not measured' 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 
;
_cod_original_sg_symbol_H-M      P3(2)21
_cod_database_code               4504458