Gradual Transition from NH···Pyridyl Hydrogen Bonding to the NH···O Tape Synthon in Pyridyl Ureas
Byrne, Peter; Turner, David R.; Lloyd, Gareth O.; Clarke, Nigel; Steed, Jonathan W.; Crystal Growth & Design 8 (2008) 3335–; doi:10.1021/cg800247f

data_4503671
_publ_section_title
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 Gradual Transition from NH&#x00B7;&#x00B7;&#x00B7;Pyridyl Hydrogen
 Bonding to the NH&#x00B7;&#x00B7;&#x00B7;O Tape Synthon in Pyridyl Ureas
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_journal_issue                   9
_journal_name_full               'Crystal Growth &amp; Design'
_journal_page_first              3335
_journal_paper_doi               10.1021/cg800247f
_journal_volume                  8
_journal_year                    2008
_chemical_formula_moiety         'C18 H16 N6 O2'
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_computing_cell_refinement       Saint
_computing_data_collection       Smart
_computing_data_reduction        Saint
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_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
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_diffrn_measurement_device_type  Smart-1K'
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_diffrn_radiation_source         'fine-focus sealed tube'
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_exptl_absorpt_coefficient_mu    0.104
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.499
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plates
_exptl_crystal_F_000             364
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_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0933P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
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_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            cg800247f_si_009.cif
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_cod_original_cell_volume        771.8(6)
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