Ab Initio Study of Polonium
Abstract
Polonium is the only element with a simple cubic (sc) crystal structure. Atoms in solid polonium sit at the corners of a simple cubic unit cell and no where else. Polonium has a valence electron configuration 6s{sup 2}6p{sup 4} (Z = 84). The low temperature {alpha}phase transforms into the rhombohedral (trigonal) {beta} structure at {approx}348 K. The sc {alpha}Po unit cell constant is a = 3.345 A. The beta form of polonium ({beta}Po) has the lattice parameters, a{sub R} = 3.359 A and a rhombohedral angle 98 deg. 13'. We have performed an ab initio electronic structure calculation by using the density functional theory. We have performed the calculation with and without spinorbit (SO) coupling by using both the LDA and the GGA for the exchangecorrelations. The kpoints in a simple cubic BZ are determined by R (0.5, 0.5, 0.5), {gamma} (0, 0, 0), X (0.5, 0, 0), M (0.5, 0.5, 0) and {gamma} (0, 0, 0). Other directions of kpoints are {gamma} (0, 0, 0), X (0.5, 0, 0), R (0.5, 0.5, 0.5) and {gamma} (0, 0, 0). The SO splittings of p states at the {gamma} point in the GGA+SO scheme for {alpha}Po are 0.04 eV and 0.02more »
 Authors:
 Department of Physics, University of Malaya Kuala Lumpur, 50603 (Malaysia)
 Publication Date:
 OSTI Identifier:
 21143306
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: AIP Conference Proceedings; Journal Volume: 1017; Journal Issue: 1; Conference: PERFIK 2007: National physics conference 2007 on current issues of physics in Malaysia, Kuala Terengganu (Malaysia), 2628 Dec 2007; Other Information: DOI: 10.1063/1.2940638; (c) 2008 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ATOMS; CORRELATIONS; CUBIC LATTICES; DENSITY FUNCTIONAL METHOD; ELECTRONIC STRUCTURE; ELECTRONS; LS COUPLING; LATTICE PARAMETERS; P STATES; PHASE TRANSFORMATIONS; POLONIUM; SOLIDS; SPIN; VALENCE
Citation Formats
Zabidi, Noriza Ahmad, Kassim, Hasan Abu, and Shrivastava, Keshav N. Ab Initio Study of Polonium. United States: N. p., 2008.
Web. doi:10.1063/1.2940638.
Zabidi, Noriza Ahmad, Kassim, Hasan Abu, & Shrivastava, Keshav N. Ab Initio Study of Polonium. United States. doi:10.1063/1.2940638.
Zabidi, Noriza Ahmad, Kassim, Hasan Abu, and Shrivastava, Keshav N. Tue .
"Ab Initio Study of Polonium". United States.
doi:10.1063/1.2940638.
@article{osti_21143306,
title = {Ab Initio Study of Polonium},
author = {Zabidi, Noriza Ahmad and Kassim, Hasan Abu and Shrivastava, Keshav N.},
abstractNote = {Polonium is the only element with a simple cubic (sc) crystal structure. Atoms in solid polonium sit at the corners of a simple cubic unit cell and no where else. Polonium has a valence electron configuration 6s{sup 2}6p{sup 4} (Z = 84). The low temperature {alpha}phase transforms into the rhombohedral (trigonal) {beta} structure at {approx}348 K. The sc {alpha}Po unit cell constant is a = 3.345 A. The beta form of polonium ({beta}Po) has the lattice parameters, a{sub R} = 3.359 A and a rhombohedral angle 98 deg. 13'. We have performed an ab initio electronic structure calculation by using the density functional theory. We have performed the calculation with and without spinorbit (SO) coupling by using both the LDA and the GGA for the exchangecorrelations. The kpoints in a simple cubic BZ are determined by R (0.5, 0.5, 0.5), {gamma} (0, 0, 0), X (0.5, 0, 0), M (0.5, 0.5, 0) and {gamma} (0, 0, 0). Other directions of kpoints are {gamma} (0, 0, 0), X (0.5, 0, 0), R (0.5, 0.5, 0.5) and {gamma} (0, 0, 0). The SO splittings of p states at the {gamma} point in the GGA+SO scheme for {alpha}Po are 0.04 eV and 0.02 eV while for the {beta}Po these are 0.03 eV and 0.97 eV. We have also calculated the vibrational spectra for the unit cells in both the structures. We find that exchanging of a Po atom by Pb atom produces several more bands and destabilizes the {beta} phase.},
doi = {10.1063/1.2940638},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1017,
place = {United States},
year = {Tue May 20 00:00:00 EDT 2008},
month = {Tue May 20 00:00:00 EDT 2008}
}

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