Quantum chemical calculations have been performed to compute optimized molecular geometry, atomic charges and vibrational characteristics for 2-hydroxy-3-methoxy-N-(2-chloro-benzyl)-benzaldehyde-imine (C15H14O2NCl) in the ground state using restricted Hartree-Fock (RHF) and density functional theory (DFT) methods with 6-31+G** basis set. NBO analysis is also performed. The IR and Raman spectra ...

it seems that the general applicability of the quantum theory of atoms in molecules (qtaim) oncharacterizing the bonded interactions is still questionable even afier 30 years since its formulation. fordemonstrating the generality of bonding schemes in qta im, ea( isomers were chosen as the modelsystems and the results from molecular charge density analysis and vibrational normal modes werecompa...

In this paper, homotopy perturbation and modified Lindstedt-Poincare methods are employed for nonlinear free vibrational analysis of simply supported and double-clamped beams subjected to axial loads. Mid-plane stretching effect has also been accounted in the model. Galerkin's decomposition technique is implemented to convert the dimensionless equation of the motion to nonlinear ordinary differ...

the interaction of dopamine and cysteine for formation of 5-s-cysteinyldopamine are investigated at thehartree-fock level theory. the structural and vibrational properties of 5-s-cysteinyldopamine are studiedat level of hf/6-31g*.interaction energy ( ae) is calculated -771.6923 kcal/mol rotational energy andthermodynamic parameters around two bond have been determined using hf/3-21g. changes of...

quasicrystals are a group of materials with the quasi-periodic structure, and since their discovery in 1980 their specially interesting physical properties have attracted the attention of many researchers. the lack of translational periodicity makes the numerical calculations of their physical properties much more difficult than the crystalline solids. in this work we present a detailed numeric...

Modern ab initio and multiscale methods enable the simulation of vibrational properties of very large molecules. Within the harmonic approximation, the traditional generation of the spectra based on the force field diagonalization can become inefficient due to the excessive demands on computer time and memory. The present study proposes to avoid completely the matrix diagonalization with a dire...

We have characterized the vibrational predissociation (VP) of the Ne(2)Br(2) van der Waals complex using time- and frequency-resolved pump-probe spectroscopy. After exciting Br(2) within the complex to a vibrational level 16<or=nu(')<or=23 in the B state, we follow the flow of halogen vibrational energy to the van der Waals modes in real time by recording the time-dependent behavior of Ne(2)Br(...