A 'quasi-diabatic' representation for inelastic collisions Application to the scattering of He+ by Ne

A 'quasi-diabatic' representation based on LCAO-MO-SCF electronic wavefunctions, satisfying to a large extent Lichten's original suggestion and Smith's theoretical definition for diabatic states, is introduced. Potential energy curves of the HeNe+ molecular ion have been obtained in this framework and subsequently used in computing differential cross sections for the inelastic scattering of He+ by Ne in the Landau-Zener two states approximation. The shape and the location of the crossings of the potential energy curves agree with the experimental predictions of Coffey et al. and Baudon et al. The transition matrix element at the outer crossing is calculated as an electrostatic interaction term and the value obtained is 0.26 eV. Some arguments are presented which suggest that the experimental values are overestimated.

[1]  R. Lefebvre.  Preparation and decay of initial states in intramolecular radiationless processes , 1971 .

[2]  F. Smith,et al.  COLLISION SPECTROSCOPY. IV. SEMICLASSICAL THEORY OF INELASTIC SCATTERING WITH APPLICATIONS TO He$sup +$ + Ne. , 1971 .

[3]  A. Bandrauk,et al.  Analytic predissociation linewidths from scattering theory , 1970 .

[4]  J. Baudon,et al.  Differential measurements on ion-atom collisions in the energy range 500 eV-3000 eV. II. He+ on Ne, Ar, Kr, Xe and Ne+ on He collisions , 1970 .

[5]  W. Aberth,et al.  COLLISION SPECTROSCOPY OF THE SYSTEM Li$sub 2$ . , 1970 .

[6]  F. Smith,et al.  Collision spectroscopy. II - Inelastic scattering of He/plus/ by Ne , 1969 .

[7]  R. P. Marchi.  Semiclassical theory of elastic perturbations. , 1969 .

[8]  W. Kołos,et al.  Theoretical Investigation of the Lowest Double‐Minimum State E, F 1Σg+ of the Hydrogen Molecule , 1969 .

[9]  F. Smith,et al.  DIABATIC AND ADIABATIC REPRESENTATIONS FOR ATOMIC COLLISION PROBLEMS. , 1969 .

[10]  H. Lefebvre-Brion.  Theoretical study of homogeneous perturbations. II. Least-squares fitting method to obtain , 1969 .

[11]  J. T. Hougen,et al.  Avoided Crossings in Bound Potential‐Energy Curves of Diatomic Molecules: Derivation and Analysis of the Vibrational Hamiltonian , 1968 .

[12]  J. Bardsley.  Configuration interaction in the continuum states of molecules , 1968 .

[13]  T. F. O'Malley.  SLOW HEAVY-PARTICLE COLLISION THEORY BASED ON A QUASIADIABATIC REPRESENTATION OF THE ELECTRONIC STATES OF MOLECULES. , 1967 .

[14]  A. C. Wahl,et al.  Single‐Configuration Wavefunctions and Potential Curves for the Ground States of He2, Ne2, and Ar2 , 1967 .

[15]  P. Felenbok,et al.  ÉTUDE THÉORIQUE DES PERTURBATIONS HOMOGÈNES : I. APPLICATION AUX INTERACTIONS Π–Π ET Δ–Δ DE NO , 1966 .

[16]  W. Lichten.  Resonant Charge Exchange in Atomic Collisions , 1963 .

[17]  A. D. McLachlan,et al.  Dynamical Jahn‐Teller Effect in Hydrocarbon Radicals , 1960 .

[18]  C. Zener.  Non-Adiabatic Crossing of Energy Levels , 1932 .