Analytical Potential Energy Function for the Ground State X^{1} Sigma^+ of LaCl

The equilibrium geometry, harmonic frequency and dissociation energy of lanthanum monochloride have been calculated at B3LYP, MP2, QCISD(T) levels with energy-consistent relativistic effective core potentials. The possible electronic state and reasonable dissociation limit for the ground state are determined based on atomic and molecular reaction statics. Potential energy curve scans for the ground state X^{1} Sigma^+ have been carried out with B3LYP and QCISD(T) methods due to their better performance in bond energy calculations. We find the potential energy calculated with QCISD(T) method is about 0.5 eV larger than dissociation energy when the diatomic distance is as large as 0.8 nm. The problem that single-reference ab initio methods don't meet dissociation limit during calculations of lanthanide heavy-metal elements is analyzed. We propose the calculation scheme to derive analytical Murrell-Sorbie potential energy function and Dunham expansion at equilibrium position. Spectroscopic constants got by standard Dunham treatment are in good agreement with results of rotational analyses on spectroscopic experiments. The analytical function is of much realistic importance since it is possible to be applied to predict fine transitional structure and study reaction dynamic process.Comment: 10 pages, 1 figure, 3 table

Non-magnetic Stern-Gerlach Experiment from Electron Diffraction

Using the wave nature of the electrons, we demonstrate that a transverse spin current can be generated simply by the diffraction through a single slit in the spin-orbital coupling system of the two-dimensional electron gas. The diffracted electron picks up the transverse momentum. The up spin electron goes one way and the down spin electron goes the other, producing the coherent spin current. In the system of spin-orbital coupling $\sim10^{-13}$ eV$\cdot$m, the \emph{out-of-plane} component of the spin of the electron can be generated up to 0.42 $\hbar$. Based on this effect, a novel device of grating to distill spin is designed. Two first diffraction peaks of electron carry different spins, duplicating the non-magnetic version of Stern-Gerlach experiment. The direction of the spin current can be controlled by the gate voltage with low energy cost.Comment: 4 pages, 4 figure