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Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
The most stable tautomer of 3-amino-1,2,4-triazin-5-one and its structural geometry
M R Jalilian1, Mansoureh Zahedi-Tabrizi
1Department of Chemistry, Faculty of Science, Al-Zahra University, Vanak, Tehran, Iran. jalilianiraj@yahoo.com
Abstract:
With the purpose of finding predominant tautomer among five possible isomers of 3-amino-1,2,4-triazin-5-one and to refine some unreasonable structural parameters previously reported from X-ray diffraction measurements, a series of ab initio calculations were carried out. In agreement with previous results, our calculations show that 3-amino-1,2,4-triazin-5(2H)-one tautomer is the most stable one. Concerning the predominant tautomer, comparisons were made between structural parameters calculated and those obtained by X-ray crystallographic analysis. The structural geometry of the main skeleton of the molecule calculated by the B3LYP/6-311++G** density functional method are generally in good agreement with the experimental values, and those predicted by Pauling's method. Bond distance values calculated are in excellent agreement with the conventionally accepted bond lengths in similar molecules. All bond distances, bond angles, dihedral angles, dipole moments and rotational constants are presented.
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