The development of a full range analytical interatomic potential

Abstract

A chronological account is given to the development of a full range interatomic potential. Starting with a simple phenomenological model, the terms in the model are gradually modified, so that...

An accurate potential model for the a3Σu+ state of the lithium dimer

“…where V short (R) and a can be taken directly from V TT2 of ref. 18, since this part of the calculation is exactly the same. Thus…”

“…This can be done without affecting D e and R e by defining V STT2 ( R ) = V short ( R ) + (1 − e − αR ) V STT ( R ),where V short ( R ) and α can be taken directly from V TT2 of ref. 18, since this part of the calculation is exactly the same. Thuswithandwhere Z A , Z B are the nuclear charges and E A , E B are the energies of the separate atoms, and E ua is the united atom energy with the same electronic state of the separate atoms.…”

“…In the present paper a model for the interatomic potential V(R) (R is the internuclear distance) of Li 2 in the a 3 S u + state is described, which is based on a simple transformation of the TT potential model. 17,18 This potential model V(R) is the sum of an attractive part and a repulsive part. The attractive part consists of the damped dispersion series.…”

Universal Pairwise Interatomic van der Waals Potentials Based on Quantum Drude Oscillators

“…Moreover, the LJ potential is notorious for its lack of flexibility and very limited quantitative accuracy. , On the other hand, the celebrated Tang–Toennies (TT) potentials − are derived from first principles and yield high accuracy for dimers including noble gases and group II elements. To achieve such an accuracy, the TT potentials employ 5 to 9 parameters depending on the exact flavor . Setting these parameters requires knowledge of R e and D e for each vdW-bonded dimer, , which prevents a generalization of the TT models to the whole periodic table.…”

“…However, these parameters can be determined unambiguously only for relatively simple vdW-bonded systems, such as noble-gas dimers or crystals. Moreover, the LJ potential is notorious for its lack of flexibility and very limited quantitative accuracy. , On the other hand, the celebrated Tang–Toennies (TT) potentials − are derived from first principles and yield high accuracy for dimers including noble gases and group II elements. To achieve such an accuracy, the TT potentials employ 5 to 9 parameters depending on the exact flavor .…”