Original Articles: 2016 Vol: 8 Issue: 4
Quantum Chemical Studies on hydrogen bonding interaction of Pyrimidine and Water
Abstract
Structure and stability of the complexes formed between pyrimidine and water molecules have been completely
investigated in the present study using by second order Moller-Plesset (MP2) and density functional theory (DFT)
on the basis set 6-311++G(d,p). Nine reasonable geometries on the potential energy hyper surface of the pyrimidine
and water are considered: two each are with two, three and four water molecules and one each with one, five and
six water molecules. Optimized geometries and hydrogen binding energies for various structures have been
estimated. Hydrogen binding energies and bond distances as well as the vibrational characteristics show that as the
number of water molecules increases stability of the complexes increases and the bond length between N and H
decreases. The ring-breathing mode ν1 of the reference system Pd was chosen as a marker band to probe the degree
of hydrogen bonding.