POLALMM: A program to compute polarizabilities for nominal one-electron systems using the Lagrange-mesh method

Abstract

We present a program to compute polarizabilities of nominal one-electron systems using the Lagrange-mesh method (LMM) (Baye, 2015) [1], that was used by Filippin et al., (2018). A semiempirical-core-potential approach is implemented, ultimately solving a Dirac-like equation by diagonalizing the corresponding Hamiltonian matrix. In order to build the core potential, the core orbitals are obtained from independent calculations using the Grasp2018 package (Fischer et al., 2019). Therefore we provide an easy-to-use interface between the Grasp2018 package and the LMM complete finite basis, allowing to switch easily from one one-electron basis to the other. Program summaryProgram Title: POLALMMCPC Library link to program files:http://dx.doi.org/10.17632/6mw5gdwfkt.1Licensing provisions: MIT licenseProgramming language: Fortran90Nature of problem: Determination of the dipole and quadrupole polarizabilities.Solution method: We combine a semiempirical-core-potential approach with the numerical Lagrange-mesh method to solve a Dirac-like one-electron equation [2]. The building of the core potential requires the prior knowledge of core orbitals provided by Grasp [3]. Two free parameters are optimized by fitting the computed single-electron valence energies to their experimental reference value.