Density functional theory (DFT) calculations have been performed to study properties of chitosan (Chit) as a possible vehicle for carrying metformin (Met) drug. To this aim, the singular molecules of Met and Chit have been first optimized and sixteen possible bimolecular complexes have been subsequently constructed and optimized to obtaine the stabilized interacting structures. Two bimolecular ...

Emission and absorption spectra of many organic dyes in liquid solutions depend on the local electric fields generated by the surrounding polar solvent molecules. This “solvation effect” is a result of intermolecular solutesolvent interaction forces (such as dipole-dipole or dipole-induced dipole) that tend to stretch molecular bonds and shift charge distribution on molecules, altering the ener...

In this work, we report the results of a series of density functional theory (DFT) based ab initio molecular dynamics (AIMD) simulations of ambient liquid water using a hierarchy of exchange-correlation (XC) functionals to investigate the individual and collective effects of exact exchange (Exx), via the PBE0 hybrid functional, non-local van der Waals/dispersion (vdW) interactions, via a fully ...

This study investigated the effects of solvents’ polarities on the geometry and electronic properties of 2-(2-nitrovinyl) furan, (NVF). The investigation was carried via theoretical approach, using an ab-initio [Hartree Fock (HF/6-31G*)] and Density Functional Theory (DFT/B3LYP/6-31G*).The properties investigated are optimized structures, energy gaps (ELUMO – EHOMO) and as...

The dipole-dipole interaction influences nanoscopic matter by fixing the patterns of permanent, displacive, and induced dipole moments, subject to constraints of molecular size and other short range interactions. Prediction of these arrangements is a challenging problem. The eigenvector of maximum eigenvalue of the dipole-dipole interaction matrix can provide insights and sometimes a complete s...

nbo analysis, hybrid density functional theory (b3lyp/6-311+g**) and ab initio molecular orbital (hf/6-311+g**) based methods were used to study the anomeric effects (ae), electrostatic interactions, dipole-dipole interactions and steric repulsion effects on the conformational properties of 2-methoxy- (1), 2-methylthio- (2), 2-methylseleno- (3), 2-fluoro- (4), 2-chloro- (5) and 2-bromocyclohexa...

Density functional theory (DFT) molecular dynamics simulations of a thin (approximately 15 A) water film on NaCl(001) have been performed, with the aim of understanding the structural and dynamic properties of this important interfacial water system. The interaction of the water film with the surface orders the water molecules in the immediate vicinity of the interface. This is reflected by osc...

Practical applications of guest-host liquid crystal systems are critically dependent on the alignment of the guest species within the liquid crystal host. UV/Vis absorption spectroscopy shows that the 1,5-dihydroxy-2,6-bis-(4-propylphenyl)-9,10-anthraquinone dye aligns within the E7 nematic host, giving an experimental dichroic ratio of 9.40 and dye order parameter of 0.74. This alignment was m...

The rotational spectra of anisole and of benzaldehyde were investigated in supersonic expansion at frequencies up to 41 GHz, and at room temperature in the millimetre-wave region, from 170 to 330 GHz. Accurate spectroscopic constants for the parent isotopomers in the ground vibrational state and for the first excited torsional state were determined for both molecules. The supersonic expansion s...

Recent experiments on liquid water show collective dipole orientation fluctuations dramatically slower than expected (with relaxation time > 50 ns) [D.P. Shelton, Phys. Rev. B 72, 020201(R) (2005)]. Molecular dynamics simulations of extended simple point charge (SPC/E) water show a large vortexlike structure of the dipole field at ambient conditions surviving over [J. Higo, Proc. Natl. Acad. Sc...