Structural stability analysis of Wigner crystal with Gaussian and Yukawa-type positive background

Abstract

Calculations of the ground-state energies of Wigner crystals having simple cubic (sc), body-centered cubic (bcc), face-centered cubic (fcc), diamond, and perovskite structures and (hence) the analysis of relative stability of Wigner crystals of various different structures are reported. The positive background is represented by a periodic array of Gaussians and Yukawa-type distribution. The effects on stability of the perturbation due to the underlying lattice have been demonstrated. Among the structures, the bcc lattice still remains the most stable known arrangement and the Yukawa-type background leads to a lower ground state energy value compared to a Gaussian type. The calculations are done for the range of the density parameter rs corresponding to low densities for the above two cases. The range of low-density region favorable for Wigner crystallization is found to be above rs=20. The role of correlation energy is suitably taken into account. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001