A Quantum Monte Carlo Study of Lanthanum

Nagat Elkahwagy, Atif Ismail, Sana Maize, Kamal Reyad Mahmoud

hysics Department, Faculty of Science, Menoufia University, Shebin El-Kom, Egypt.
Physics Department, Faculty of Science, Kafrelsheikh University, Kafr El-Sheikh, Egypt.

DOI: 10.4236/wjcmp.2013.34034                

Abstract

Pseudopotential calculations of the ground state energies of the Lanthanum neutral atom, first and second corresponding cations by means of the variational Monte Carlo (VMC) and the diffusion Monte Carlo (DMC) methods are performed. The first and the second ionization potentials have been calculated for Lanthanum. The obtained results are satisfactory and comparable with the available experimental data. Studying the DMC energy of the La atom at different time steps, gave us a time step error of the order 0.0019 Hartree for the smallest time step, τ = 0.0001 Hartree^-1, and -0.0104 Hartree for the largest time step, τ = 0.01 Hartree^-1. This paper demonstrates the ability of extending the QMC method for lanthanides and obtaining highly accurate results.

Keywords

Variational Monte Carlo; Diffusion Monte Carlo; Lanthanum; Hartree; Time Step

Conflicts of Interest

The authors declare no conflicts of interest.

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