QUASI-CLASSICAL EXPRESSION FOR PARAMETERS WHICH DETERMINE NONADIABATIC TRANSITIONS IN A Z1EZ2 BASIS

An asymptotic theory of quasiclassical type is constructed for the quasistationary states and branch points of terms in the problem of two Coulomb centers. In the adiabatic approximation of atomic collision theory, the branch points and the parameters of quasistationary states, respectively, determine the electron transitions between two bound states and between a bound state and the continuous spectrum. © 1990 The American Physical Society.