Pan Shou-Fu

An interpolation solution of the Abel transformation for use in optically-thick, cylindrically-symmetric plasmas

Abstract An interpolation to obtain the radial emission coefficient for optically-thick, cylindrically-symmetric plasmas is proposed. Using the interpolation, the generalized Abel equation may be separated into a system of linear algebraic equations. The coefficient matrix of the system is an upper Heisenberg matrix. An example is evaluated using both our interpolation and Youngs iteration. It is shown that the interpolation is precise and easier to apply than Youngs iteration.

Multi-reference calculations of the photodissociation of HSCH3 molecule

This paper performs multi-reference second-order perturbation theory calculations on the ground state and a number of low-lying excited states of HSCH3 molecule, and calculates the vertical excitation energies and low-energy potential-energy curves, based on which the photodissociation channels of HSCH3 at 193,222,248 nm are clarified.

Electron impact excitation of tetrasulfur S4 molecule

Electron impact excitation of tetrasulfur S4 molecule is investigated in this work using R-matrix method. The twelve low-lying electronic states are used in close-coupling expansion to represent the target states, and the integral cross sections for elastic scattering and excitation into the six lowest electronic states are calculated.

Structure and stability of various states of the EuC and EuC2 molecules

B3LYP level density functional theory (DFT) and multiconfiguration self-consistent-field (MCSCF) level ab initio method calculations have been performed on the basis of relativistic effective core potentials to investigate the nature of EuC and EuC2 molecules. The computed results indicate that the ground states of EuC and EuC2 are 12∑+ and 8A2, respectively. Dissociation potential energy curves of the low-lying electronic states of EuC have been calculated using the MCSCF method, and the same level calculation on EuC2 indicates that the dissociation energy of EuC2 of ground state compares well with the available experimental data. The bond characteristic is also discussed using Mulliken populations.

Electronic states of C20 isomers

Using quantum chemistry ab initio method, geometry optimization of the singlet and triplet electronic states are performed for three isomers (ring, bowl and cage structures) of C20. From the optimized geometries, MP2 calculation gives a result which does not agree with Hunds rule, i.e. the singlet state has a lower energy for all the three isomers. Further more, total charge densities and electrostatic potentials of three isomers are given by the UHF wavefunctions, the results indicate negative charges located in the central area of cage and bowl structures and the bond character of ring structure is analysed.

Electronic Curves Crossing in Methyl Iodide by Spin–Orbit Ab Initio Calculation

An ab initio investigation of electronic curve crossing in a methyl iodide molecule is carried out using Spin–Orbit multiconfigurational quasidegenerate perturbation theory. The one-dimensional rigid potential curves and optimized effective curves of low-lying states, including Spin–Orbit coupling and relativistic effects, are calculated. The Spin–Orbit electronic curve crossing between 3Q0+and 1Q1, and the shadow minimum in potential energy curve of 3Q0+ at large internuclear distance are found in both sets of the curves according to the present calculations. The crossing position is in the range of RC–I = 0.2370 ± 00001 nm. Comparisons with other reports are presented.

Spin?orbit ab initio curves of 80 Se2+ ion and the assignment of photoelectron spectra of 80 Se2 molecule

This paper carries out ab initio calculations to study the 80 Se2(X3?g-) state and 80 Se2+(X2 IIg), 80 Se2+(a4 IIg) states by using completed active space self-consistent field and multi-reference second order perturbation theory. The electronic curves of these states including spin?orbit coupling are calculated, and then the spectroscopic parameters are obtained. The photoelectron spectra of 80 Se2 molecule in gas phase are assigned according to Franck?Condon analysis based on calculated potential energy curves. The ionization energies of 80 Se2 molecule are determined by the present calculation.

Quantum Electrodynamics Theory of Laser Assisted Recombination

Using a formal scattering theoretical approach, we develop a nonperturbative quantum electrodynamics theory to describe laser assisted recombination (LAR), in which an electron initially in the quantized Volkov state recombines with an ion and emits a high-energy photon with frequency defined by energy conservation laws. The transition probability is expressed as an analytic closed form and the spectrum of LAR reflects mainly the properties of general Bessel functions. For the case of a fast electron the LAR spectrum is confined in a well-defined range, while for a slow electron, the LAR spectrum exhibits a double-plateau structure.

Electron collision cross sections and rate coefficients for the Na-like Cu ion

Collision cross sections are calculated using the R-matrix method for excitations between the three lowest LS states for Na-like Cu ion. The complex resonance structures are investigated. The collision rate coefficients have been calculated assuming a Maxwellian distribution of electron-impact energies. The results of the collision cross sections are in good agreement with those of the other theory.Collision cross sections are calculated using the R-matrix method for excitations between the three lowest LS states for Na-like Cu ion. The complex resonance structures are investigated. The collision rate coefficients have been calculated assuming a Maxwellian distribution of electron-impact energies. The results of the collision cross sections are in good agreement with those of the other theory.

Variability of Multiphoton Detachment Rate Versus Laser Intensity

With the help of a model calculation based on the R-matrix - Floquet theory, the variability of multiphoton detachment rate versus laser intensity is in detail investigated. A number of interesting regularities, which can not be understood in the lowest order perturbation theory, is found out and interpreted.