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Ab Initio Electronic Structure Calculations for Nuclear Materials
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J.-P. Crocombette and F. Willaime Commissariat a I’Energie Atomique, DEN, Service de Recherches de Metallurgie Physique, Gif-sur-Yvette, France © 2012 Elsevier Ltd. All rights reserved.
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1.08.5.2.1 |
Bulk electronic structure |
243 |
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1.08.5.2.2 |
Point defects |
244 |
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1.08.5.2.3 |
Oxygen clusters |
244 |
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1.08.5.2.4 |
Impurities |
245 |
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1.08.6 |
Conclusion |
245 |
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References |
246 |
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Abbreviations |
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bcc |
Body-centered cubic |
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CTL |
Charge transition levels |
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DFT |
Density functional theory |
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DLTS |
Deep level transient spectroscopy |
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EPR |
Electron paramagnetic resonance |
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fcc |
Face-centered cubic |
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FLAPW |
Full potential linearized augmented plane waves |
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FP |
Fission products |
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GGA |
Generalized gradient approximation |
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LDA |
Local density approximation |
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LSD |
Local spin density approximation |
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LVM |
Local vibrational modes |
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PAW |
Projector augmented waves |
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PL |
Photo-luminescence |
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RPV |
Reactor pressure vessel |
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SIA |
Self-interstitial atom |
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SQS |
Special quasi-random structures |
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TD-DFT |
Time dependent density functional theory |
Electronic structure calculations did not start with the so-called ab initio calculations or in recent years. The underlying basics date back to the 1930s with an understanding of the quantum nature of bonding in solids, the Hartree and Fock approximations, and the Bloch theorem. A lot was understood of the electronic structure and bonding in nuclear materials using semiempirical electronic structure calculations, for example, tight binding calculations.1 The importance ofthese somewhat historical calculations should not be overlooked. However, in the following sections, we focus on ‘ab initio’ calculations, that is, density functional theory (DFT) calculations. One must acknowledge that ‘ab initio calculations’ is a rather vague expression that may have different meanings depending on the community. In the present chapter we use it, as most people in the materials science community do, as a synonym for DFT calculations.
The popularity of these methods stems from the fact that, as we shall see, they provide quantitative results on many properties of solids without any adjustable parameters, though conceptual and technical difficulties subsist that should be kept in mind. The presentation is divided as follows. Methodologies and tools are briefly presented in the first section. The next two sections focus on some examples of ab initio results on metals and alloys on one hand and insulating materials on the other.