Shell-model and first-principles calculations of vibrational, structural and ferroelectric properties of KH_2PO_4
Autor: | R. E. Menchón, F. Torresi, J. Lasave, S. Koval |
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Jazyk: | angličtina |
Rok vydání: | 2022 |
Předmět: | |
Zdroj: | Condensed Matter Physics, Vol 25, Iss 4, p 43709 (2022) |
Druh dokumentu: | article |
ISSN: | 1607-324X 2224-9079 |
DOI: | 10.5488/CMP.25.43709 |
Popis: | We develop a shell model (SM) for potassium dihydrogen phosphate (KDP) which is fitted to ab initio (AI) results that include nonlocal van der Waals corrections. The SM is comprehensively tested by comparing results of structural, vibrational and ferroelectric properties with AI and experimental data. The relaxed structural parameters are in very good agreement with the AI results and the available experimental data. The Γ-point phonons and the total phonon densities of states (DOSs) in the ferroelectric and paraelectric phases calculated with the developed SM are in good overall agreement with the corresponding AI and experimental data. We also compute the effective Debye temperature as a function of T which shows good accordance with the corresponding AI and experimental results. Classical molecular dynamics (MD) simulations obtained with the developed SM show a FE-PE phase transition at ≈ 360 K in remarkable agreement with ab initio MD calculations. |
Databáze: | Directory of Open Access Journals |
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