Exchange-Coulomb model potential energy surfaces have been developed for the Ne-CO interaction. The initial model is a three-dimensional potential energy surface based upon computed Heitler-London interaction energies and literature results for the long-range induction and dispersion energies, all as functions of interspecies distance, the orientation of CO relative to the interspecies axis, an...

The IR and Raman spectra of the title compound have been recorded and analyzed. The harmonic vibrational wavenumbers were calculated theoretically using Gaussian09 software package. Calculations were performed by HF and DFT levels using the standard 6-31G* basis sets. The data obtained from vibrational wavenumber calculations are used to assign vibrational bands found in the IR and Raman spectr...

© 2007 American Institute of Physics, S-0031-9228-0711-020-6 When light interacts with matter, it can scatter inelastically from vibrational quantum states. During that process, photons may lose energy to, or gain it from, vibrational excitations. A change in the photon energy must produce a concomitant shift in the frequency of the scattered light (see box 1). The phenomenon, called the Raman ...

Geometric structures, bond lengths, angles, vibrational frequencies, dipole moments, proton and carbon-13 NMR isotropic chemical shifts, UV-Vis. Parameters, HOMO LUMO energies of pioglitazone molecules were studied using Gaussian09 program with DFT/B3LYP method at the 6-311G++(2d,2p) basis set. The assignments theoretical modes obtained VEDA 4 software in terms potential energy distribution (PE...

The terahertz and infrared frequency vibration modes of room-temperature ionic liquids with imidazolium cations and halogen anions were extensively investigated. There is an intermolecular vibrational mode between the imidazolium ring of an imidazolium cation, a halogen atomic anion with a large absorption coefficient and a broad bandwidth in the low THz frequency region (13-130 cm-1), the intr...

The vibrational spectra of the nucleic acid bases adenine, thymine, guanine, and cytosine are calculated in the frame of density functional theory Ž . DFT . In particular we use the Kohn]Sham scheme with gradient corrections for exchange and correlation to determine normal modes, frequencies, and intensities. The DFT results are found to be in good agreement with the experiment. Our computation...

Ž . A direct transfer of Cartesian molecular force fields FF and electric property tensors is tested on model systems and compared to transfer in internal coordinates with an aim to improve simulation of vibrational spectra for larger molecules. This Cartesian transformation can be implemented easily and offers greater flexibility in practical computations. It can be also applied for transfer o...

Based on first principles calculations, we investigate two probable types of deactivation mechanisms that hinder current efforts ofdoping ZnO p-type. (i) Passivation by Hydrogen. H prefers to bind with NO at the anti-bonding site and form NO–H complexes with abinding energy of about 1 eV. (ii) Passivation by the formation of substitutional diatomic molecules (SDM). Carbon impurities and...