Optically-stimulated desorption of 'hot' excimers from pre-irradiated Ar solids

Electronically-induced desorption from solid Ar pre-irradiated by a low-energy electron beam was investigated by activation spectroscopy methods - photon-stimulated exoelectron emission and photon-stimulated luminescence in combination with spectrally-resolved measurements in the VUV range of the spectrum. Desorption of vibrationally excited argon molecules Ar2^*(v) from the surface of pre-irradiated solid Ar was observed for the first time. It was shown that desorption of 'hot' Ar2^*(v) molecules is caused by recombination of self-trapped holes with electrons released from traps by visible range photons. The possibility of optical stimulation of the phenomenon is evidenced.Comment: The complete version of the paper will be published in Fiz. Nizk. Temp. (Low Temp. Phys.

Electron traps in solid Xe

Correlated real-time measurements of thermally stimulated luminescence and exoelectron emission from solid Xe pre-irradiated with an electron beam were performed. The study enabled us to distinguish between surface and bulk traps in solid Xe and to identify a peak related to electronically induced defects. The activation energy corresponding to annihilation of these defects was estimated by the following methods: the method of different heating rates, the initial-rise method, and the curve cleaning technique with fitting of the thermally stimulated luminescence glow curve

Relativistic separable dual-space Gaussian Pseudopotentials from H to Rn

We generalize the concept of separable dual-space Gaussian pseudopotentials to the relativistic case. This allows us to construct this type of pseudopotential for the whole periodic table and we present a complete table of pseudopotential parameters for all the elements from H to Rn. The relativistic version of this pseudopotential retains all the advantages of its nonrelativistic version. It is separable by construction, it is optimal for integration on a real space grid, it is highly accurate and due to its analytic form it can be specified by a very small number of parameters. The accuracy of the pseudopotential is illustrated by an extensive series of molecular calculations

Correct quantum chemistry in a minimal basis from effective Hamiltonians

We describe how to create ab-initio effective Hamiltonians that qualitatively describe correct chemistry even when used with a minimal basis. The Hamiltonians are obtained by folding correlation down from a large parent basis into a small, or minimal, target basis, using the machinery of canonical transformations. We demonstrate the quality of these effective Hamiltonians to correctly capture a wide range of excited states in water, nitrogen, and ethylene, and to describe ground and excited state bond-breaking in nitrogen and the chromium dimer, all in small or minimal basis sets

Simulation of thermal conductivity and heat transport in solids

Using molecular dynamics (MD) with classical interaction potentials we present calculations of thermal conductivity and heat transport in crystals and glasses. Inducing shock waves and heat pulses into the systems we study the spreading of energy and temperature over the configurations. Phonon decay is investigated by exciting single modes in the structures and monitoring the time evolution of the amplitude using MD in a microcanonical ensemble. As examples, crystalline and amorphous modifications of Selenium and $\rm{SiO_2}$ are considered.Comment: Revtex, 8 pages, 11 postscript figures, accepted for publication in PR

VIBRATIONAL RELAXATION AND INTERNAL CONVERSIONS IN THE CN RADICAL IN SOLID NEON

Author Institution: Bell LaboratoriesThe CN radicals are formed in. solid neon in two distinct trapping sites. The CN fluorescence following a selective excitation of individual vibrational levels of the $B^{2}\Sigma^{+}$ and $A^{2}\Pi$ electronic state was studied. The high vibrational levels of both the A and states can be populated by sequential two photon processes. The $A \rightarrow X, B \rightarrow X$, and $B \rightarrow$ A systems are all seen in emission. CN in the two sites shows a differential shift of $\sim 70 cm^{-1}$ between the A and B electronic states. The relaxation behaviour is governed by internal conversions between the A, B, and X vibrational manifolds and shows a strong multiphonon energy gap law