Computing the absolute Gibbs free energy in atomistic simulations: Applications to defects in solids

Cheng B, Ceriotti M. 2018. Computing the absolute Gibbs free energy in atomistic simulations: Applications to defects in solids. Physical Review B. 97(5), 054102.


Journal Article | Published | English

Scopus indexed
Author
Cheng, BingqingIST Austria ; Ceriotti, Michele
Abstract
The Gibbs free energy is the fundamental thermodynamic potential underlying the relative stability of different states of matter under constant-pressure conditions. However, computing this quantity from atomic-scale simulations is far from trivial, so the potential energy of a system is often used as a proxy. In this paper, we use a combination of thermodynamic integration methods to accurately evaluate the Gibbs free energies associated with defects in crystals, including the vacancy formation energy in bcc iron, and the stacking fault energy in fcc nickel, iron, and cobalt. We quantify the importance of entropic and anharmonic effects in determining the free energies of defects at high temperatures, and show that the potential energy approximation as well as the harmonic approximation may produce inaccurate or even qualitatively wrong results. Our calculations manifest the necessity to employ accurate free energy methods such as thermodynamic integration to estimate the stability of crystallographic defects at high temperatures.
Publishing Year
Date Published
2018-02-01
Journal Title
Physical Review B
Volume
97
Issue
5
Article Number
054102
ISSN
eISSN
IST-REx-ID

Cite this

Cheng B, Ceriotti M. Computing the absolute Gibbs free energy in atomistic simulations: Applications to defects in solids. Physical Review B. 2018;97(5). doi:10.1103/physrevb.97.054102
Cheng, B., & Ceriotti, M. (2018). Computing the absolute Gibbs free energy in atomistic simulations: Applications to defects in solids. Physical Review B. American Physical Society. https://doi.org/10.1103/physrevb.97.054102
Cheng, Bingqing, and Michele Ceriotti. “Computing the Absolute Gibbs Free Energy in Atomistic Simulations: Applications to Defects in Solids.” Physical Review B. American Physical Society, 2018. https://doi.org/10.1103/physrevb.97.054102.
B. Cheng and M. Ceriotti, “Computing the absolute Gibbs free energy in atomistic simulations: Applications to defects in solids,” Physical Review B, vol. 97, no. 5. American Physical Society, 2018.
Cheng B, Ceriotti M. 2018. Computing the absolute Gibbs free energy in atomistic simulations: Applications to defects in solids. Physical Review B. 97(5), 054102.
Cheng, Bingqing, and Michele Ceriotti. “Computing the Absolute Gibbs Free Energy in Atomistic Simulations: Applications to Defects in Solids.” Physical Review B, vol. 97, no. 5, 054102, American Physical Society, 2018, doi:10.1103/physrevb.97.054102.
All files available under the following license(s):
Copyright Statement:
This Item is protected by copyright and/or related rights. [...]

Link(s) to Main File(s)
Access Level
OA Open Access

Export

Marked Publications

Open Data IST Research Explorer

Sources

arXiv 1710.02815

Search this title in

Google Scholar