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.
Highlights
Quantum Monte Carlo (QMC) is a powerful technique by which one can perform computational electronic structure calculations with high accuracy
One of the advantages of the QMC technique is that its computational efforts scales with N3 where N is the number of electrons in the system
Quantum Monte Carlo methods have been extensively described in the literatures [9,10,11], so we give here a brief description of the two methods, the variational and diffusion Monte Carlo methods
Summary
Quantum Monte Carlo (QMC) is a powerful technique by which one can perform computational electronic structure calculations with high accuracy. One of the advantages of the QMC technique is that its computational efforts scales with N3 where N is the number of electrons in the system. Accurate calculations for extremely light atoms using QMC methods are performed by a large number of researchers [1,2,3,4]. By means of VMC and DMC methods, we have done calculations for the ground state energies of La atom and its charged cations with the hope “achieving high accuracy”. To allow the QMC calculations of this heavy atom, pseudopotential valence-only calculations have been performed, since the presence of the inert core electrons introduces a large fluctuation in the energies and this reduces the computational efficiency. Atomic units are used throughout this work unless otherwise indicated
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
