On the limitations of the DFT+U approach to energetics of actinides
Abstract
Scalar-relativistic density functional theory calculations are performed on three phases of Np within the framework of LSDA+U approach. Material properties examined include lattice parameters, atomic volumes, bulk modulus, magnetic moments, and cohesive energies. Dependence of these properties as a function of the Hubbard-type Coulomb U parameter is investigated, and it is observed that beyond the optimized value at which resulting properties compare well with experimental data, calculations suggest anomalously large changes in volumes supplemented by magnetic transitions. Several reasons that may have caused these instabilities in our calculations are discussed, and which should be considered by those resorting to DFT+U techniques for predicting phase stability in actinides and their alloys.
Additional Information
© 2012 Elsevier B.V. Received 16 October 2011. Revised 13 February 2012. Accepted 15 February 2012. Available online 17 March 2012. This work has been performed under the auspices of the US DOE by the Lawrence Livermore National Laboratory under contract No. DE-AC52–07NA27344. The authors acknowledge the Texas A & M Supercomputing Facility (http://sc.tamu.edu/), the Chemical Engineering Cluster at Texas A&M University, as well as the Texas Advanced Computing Center (TACC) at The University of Texas at Austin for providing computing resources useful in conducting the research reported in this work.Additional details
- Eprint ID
- 31439
- Resolver ID
- CaltechAUTHORS:20120511-134220017
- DE-AC52–07NA27344
- Department of Energy (DOE)
- Created
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2012-05-14Created from EPrint's datestamp field
- Updated
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2021-11-09Created from EPrint's last_modified field