Several new techniques were developed and appUed to investigate various nontrivial aspects of vibrational motion. In particular, a novel strategy for accurate determination of vibrational energy levels in the presence of intramolecular hy­ drogen bonds was proposed. A small subset of convenient internal coordinates was chosen to represent a vibrational mode of interest, while the interdependenc...

Energy decay plays a central role in a wide range of phenomena, such as optical emission, nuclear fission, and dissipation in quantum systems. Energy decay is usually described as a system leaking energy irreversibly into an environmental bath. Here, we report on energy decay measurements in nanomechanical systems based on multilayer graphene that cannot be explained by the paradigm of a system...

Electronic and vibrational structures in the S(0) (1)A(1) and S(1) (1)A(1) states of jet-cooled phenanthrene-h(10) and phenanthrene-d(10) were analyzed by high-resolution spectroscopy using a tunable nanosecond pulsed laser. The normal vibrational energies and molecular structures were estimated by ab initio calculations with geometry optimization in order to carry out a normal-mode analysis of...

Previous spectroscopically determined potentials for both H216O and NO2 are discussed. It is shown that a recent H216O potential energy surface due to D. Xie and G. Yan (1996. Chem. Phys. Lett. 248, 409), which was determined by fits to vibrational term values alone and was claimed to be more accurate than other published spectroscopically determined potentials for this system, actually gives u...

In this study, the geometries of the [SiNinHn]q and [SiCunHn]q clusters, (n = 4,5,6 and q = 0,+1,-1) complexes have been optimized to form complexes with four, five and six planar and nonplanarsubstituents, with negative, neutral or positive atomic charge, using Density FunctionalTheory (DFT) at B3LYP/6-311+G (3df, p) computational level and then their thermodynamicstability were investigated b...

Past efforts to achieve selective bond scission by vibrational excitation have been thwarted by energy thermalization. Here we report resonant photodesorption of hydrogen from a Si(111) surface using tunable infrared radiation. The wavelength dependence of the desorption yield peaks at 0.26 electron volt: the energy of the Si-H vibrational stretch mode. The desorption yield is quadratic in the ...