Many-body renormalization of forces in f -electron materials
| Autor: | Evgeny Plekhanov, Keith Refson, P. J. Hasnip, Vincent Sacksteder, Matt Probert, Cedric Weber, Stewart J. Clark |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Physics
Bulk modulus Strongly Correlated Electrons (cond-mat.str-el) Condensed matter physics Ab initio FOS: Physical sciences chemistry.chemical_element Matsubara frequency 02 engineering and technology Electron 021001 nanoscience & nanotechnology 01 natural sciences Renormalization Samarium Condensed Matter - Strongly Correlated Electrons Cerium chemistry 0103 physical sciences CASTEP Condensed Matter::Strongly Correlated Electrons 010306 general physics 0210 nano-technology |
| Zdroj: | Phys. Rev. B Plekhanov, E, Hasnip, P, Sacksteder, V, Probert, M, Clark, S J, Refson, K & Weber, C 2018, ' Many-body renormalization of forces in f-electron materials ', Physical Review B (Condensed Matter and Materials Physics), vol. 98, no. 7, 075129, pp. 1-11 . https://doi.org/10.1103/PhysRevB.98.075129 Physical review B, 2018, Vol.98(7), pp.075129 [Peer Reviewed Journal] |
| ISSN: | 2469-9969 2469-9950 |
| DOI: | 10.1103/physrevb.98.075129 |
| Popis: | We present the implementation of Dynamical Mean-Field Theory (DMFT) in the CASTEP \emph{ab-initio} code. We explain in detail the theoretical framework for DFT+DMFT and we demonstrate our implementation for three strongly-correlated systems with $f$-shell electrons: $\gamma$-cerium, cerium sesquioxide Ce$_{2}$O$_{3}$ and samarium telluride SmTe by using a Hubbard I solver. We find very good agreement with previous benchmark DFT+DMFT calculations of cerium compounds, while for SmTe, which was never studied within DFT+DMFT before to the best of our knowledge, we show the improved agreement with the experimental structural parameters as compared with LDA. Our implementation works equally well for both norm-conserving and ultra-soft pseudopotentials, and we apply it to the calculation of total energy, bulk modulus, equilibrium volumes and internal forces in the two cerium compounds. In Ce$_{2}$O$_{3}$ we report a dramatic reduction of the internal forces acting on coordinates not constrained by unit cell symmetries. This reduction is induced by the many-body effects, which can only be captured at the DMFT level. In addition, we derive an alternative form for treating the high-frequency tails of the Green function in Matsubara frequency summations. Our treatment allows a reduction in the bias when calculating the correlation energies and occupation matrices to high precision. Comment: 11 pages, 7 figures, CASTEP DMFT reference paper |
| Databáze: | OpenAIRE |
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