Natural population analysis was carried out for EDB. Negative characters for N and O atoms in the N-C-(H)•••O-I conjunction and positive character for H atom confirms the hydrogen bonding between two (three) molecules.

The energy gaps are largely responsible for the chemical and spectroscopic properties of the molecules. LUMO–HOMO energy gap in gaseous phase is accordance to R1>R3>R2. These trend is accordance to experimental ...

to investigate the intramolecular hydrogen bonding (IHB) present

in its structure. The strength and nature of IHB in the optimized structure of 5NSA were studied in

detail by means of the atoms in molecules (AIM) and the natural bond orbital (NBO...