The complex coordinate scattering theroy and its application to the study of the surface asymmetry effect in helium diffraction from copper

Abstract

The Complex Coordinate Scattering Theory is reformulated for the general case of a time-independent Hamiltonian. It is applied to scattering of He atoms from a Cu(115) crystal surface by constracting the Green operator for the T-matrix from the eigenvectors of both the complex scaled Hamiltonian and its transposed ("right" and ''left'' eigenvectors), which are different in this case. The weakly asymmetric corrugation function describing the (1 15) face of Cu is shown to cause a strong dependence of the calculated diffraction intensities upon the direction of the incident atomic beam. The calculated transition probabilities are in excellent agreement with the experimentally measured ones, previously obtained by Perreau and Lapujoulade. We show that additional information about the gas atomhrface physisorption interaction potential can be obtained if the incident angle of the atomic beam (the angles between the beam and the surface normal) is changed from y to -7 . 0 1993 John Wiley & Sons. Inc.

Simple Closed-Form Expression for Penning Reaction Rate Coefficients for Cold Molecular Collisions by Non-Hermitian Time-Independent Adiabatic Scattering Theory

“…In this paper, we present a new uncomplicated expression and its derivation for the reaction rate coefficients based on adiabatic variational theory , and time-independent non-Hermitian scattering theory as previously developed by Moiseyev and colleagues for atomic and molecular scattering from solid surfaces, − to electron scattering from molecules, − and to interatomic/intermolecular Coulombic decay (ICD) . We show that it is not required to take into consideration in the calculations the different products of the reaction involving real potential energy surfaces (PESs).…”