Analytic Potential Energy Function for Doubly Charged Ions HBe^(2+), HB^(2+), and HF^(2+)

It is well known that the potential curve of ground state for almost all neutral diatomic molecules has only one minimum.However,the doubly charged diatomic ions may have both potential minimum and maximum or singly repulsive branch.In order to describe the potential of this kind of diatomic ions,two of the authors Zhu and Wang have proposed a new analytical potential function with four parameters ai(i=l,...,4),andρ=R-R_(min) for those with both minimum and maximum,andρ=R for those with singly repulsive branch.The present work has derived this new potential function for HBe^(2+)with R_(min)=0.182 nm,R_(max)=0.335 nm andΔE=E_(max)-E_(min)=0.84 eV,and for HBe2+with R_(min)=0.147 nm,R_(max)=0.185 nm andΔE=E_(max)-E_(min)=0.062 eV.It is found that the potential for HF^(2+)is one with singly repulsive branch.The dissociation limits,parameters ai(i=1,...,4),force constants and spectroscopic data of these ions all are given out.

Influence of the reagent vibration on the stereodynamics of the reactions D^-+H_2 and H^-+D_2

Employing the quasi-classical trajectory method and the potential energy surface of Panda and Sathyamurhy [Panda A N and Sathyamurthy N 2004 J. Chem. Phys. 121 9343], the effect of the reagent vibration on vector correlation of the ion-molecule reactions D- ＋ H2 and H- ＋ D2 is studied at a collision energy of 35.7 kcal/mol. Four generalized polarization-dependent differential cross sections （2π/σ） （dσ00/dωt）, （2π/σ） （dσ20/dσ20）, （27π/σ） （dσ22＋/dwt）, and （2π/σ）（dπ/σ） are presented in the centre-of-mass reference frame, separately. At the same time, the effects on the product angular distributions P（θr）, P（~r） and P（Oφ） of the title reactions are also analysed. The calculated results show that the scattering tendencies of the product HD, the alignment and the orientation of j^1 sensitively depend on reagent molecule vibration.

Absorption and Recurrence Spectra of Li Rydberg Atom in Perpendicular Electric and Magnetic Fields

We develop the semi-closed orbit theory from two degrees of freedom to three non-separable degrees of freedom and put forward a new model potential for the Li Rydberg atom, which reduces the study of the system to an effective one-particle problem. Using this model potential and the closed orbit theory for three degrees of freedom, we caiculate the recurrence spectra of Li Rydberg atom in perpendicular electric and magnetic fields. The closed orbits in the corresponding classicai system have also been obtained. The Fourier transformed spectra of Li atom have ailowed direct comparison between the resonance peaks and the scaied action values of closed orbits, whereas the nonhydrogenic resonance can be explained in terms of the new orbits created by the core scattering. Our result is in good agreement with the quantum spectra, which suggests that our calculation is correct.

Theoretical Study of the Stereodynamics of the Reaction C(^(3)P)+CH(X^(2)Π) and Its Isotopic Variants

Vector correlations between products and reagents of the reaction C+CH and the isotopic variant reactions are calculated by employing the quasi-classical trajectory method based on the adiabatically 1^(2)A" double−many-body-expansion potential-energy surface computed and numerically fitted by Boggio-Pasqua et al.The normalized polarization-dependent differential cross-sections and the distributions of P(θr),P(φr)and P(θr,φr)at the selected collision energy are discussed in detail.The values of the product rotational alignment parameter{P_(2)(j'⋅k)}are also calculated and plotted as functions of the collision energy in the range 0.005–0.5 eV.The computed results show that the rotational polarizations of the product present pronounced different characters as the mass substituted atom increasing.