55,190 research outputs found
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 eVm, the
\emph{out-of-plane} component of the spin of the electron can be generated up
to 0.42 . 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
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