Molecular theory ofK-vacancy production in heavy-ion-atom collisions at small impact parameters

1sσ vacancy production is calculated by approximating the 1sσ molecular wave function with an atomic 1s wave function for a chargeZ(R) centered at a distanceh(R) from the heavier nucleus.h(R) andZ(R) are determined by minimizing the 1sσ electronic energy. Previous calculations with the atomic semi-classical approximation (h=0,Z(R)=Z ₂, the target atomic number) showed that the probability of making CuK vacancies in 0.5- to 2-MeV/a.m.u. H⁺, D⁺, and He⁺+Cu collisions can be written asP(θ)=A(1+Bcosθ), whereθ is the scattering angle andA andB are constants forθ?10°. Although the recoil and dipole excitation contributions toP(θ) (which interfere destructively in the atomic theory) are independently smaller in the molecular calculations, similarB values are obtained.