Implementation of the exact semi-classical light-matter interaction - the easy way
| Autor: | Sørensen, Lasse Kragh, Kieri, Emil, Srivastav, Shruti, Lundberg, Marcus, Lindh, Roland |
|---|---|
| Rok vydání: | 2018 |
| Předmět: | |
| Zdroj: | Phys. Rev. A 99, 013419 (2019) |
| Druh dokumentu: | Working Paper |
| DOI: | 10.1103/PhysRevA.99.013419 |
| Popis: | We present an analytical and numerical solution of the calculation of the transition moments for the exact semi-classical light-matter interaction for wavefunctions expanded in a Gaussian basis. By a simple manipulation we show that the exact semi-classical light-matter interaction of a plane wave can be compared to a Fourier transformation of a Gaussian where analytical recursive formulas are well known and hence making the difficulty in the implementation of the exact semi-classical light-matter interaction comparable to the transition dipole. Since the evaluation of the analytical expression involves a new Gaussian we instead have chosen to evaluate the integrals using a standard Gau{\ss}-Hermite quadrature since this is faster. A brief discussion of the numerical advantages of the exact semi-classical light-matter interaction in comparison to the multipole expansion along with the unphysical interpretation of the multipole expansion is discussed. Numerical examples on [CuCl$_4$]$^{2-}$ to show that the usual features of the multipole expansion is immediately visible also for the exact semi-classical light-matter interaction and that this can be used to distinguish between symmetries. Calculation on [FeCl$_4$]$^{1-}$ is presented to demonstrate the better numerical stability with respect to the choice of basis set in comparison to the multipole expansion and finally Fe-O-Fe to show origin independence is a given for the exact operator. The implementation is freely available in OpenMolcas. Comment: 22 pages, 4 figures |
| Databáze: | arXiv |
| Externí odkaz: |
|