Development of free-energy calculation method based on the first-principles electronic-structure calculations and its application

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K17551
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Computational science
• Research Institution: Nagoya University
• Principal Investigator: Araidai Masaaki 名古屋大学, 未来材料・システム研究所, 助教 (20537427)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 計算物質科学 / 自由エネルギー計算 / 電子状態計算 / 機械学習

Outline of Final Research Achievements

The operating mechanism of energy-saving devices and next-generation battery is based on complex phenomena mediated by a huge variety of electronic states between a lot of atoms or molecules. In order to analyze such phenomena, I developed the free-energy calculation method, which describe statistical-mechanical properties of a system, coupled with the first-principles electronic-structure calculations. However, the developed calculation method is unexpectedly demanding to obtain realistic sampling. Therefore, I have also developed highly accurate interatomic potential based on artificial neural network. I investigated oxygen vacancy diffusion in ferroelectric BaTiO3 and gas generation in electrolyte solution by decomposition of the solution molecules by the calculation method developed in this research subject to obtain the valuable results for understanding these phenomena.

Free Research Field

計算物質科学

Academic Significance and Societal Importance of the Research Achievements

本研究課題で開発した計算手法は，従来の電子状態計算手法に熱力学的・統計力学的観点を新たに付加するものであり，実験と理論の橋渡し役として確立してきた計算物質科学の分野により強固な一面をもたらすことが期待される．本手法を適用した系，強誘電体チタン酸バリウムの酸素空孔拡散や電解液の分解によるガス発生は，その性能劣化に関連しており応用上大変重要な現象である．また，本研究課題にて開発している手法に興味を持った企業との共同研究が始まっている．したがって，「実験と理論の橋渡し役」や「産業技術に対する貢献」を目指した本研究課題は学術的にも社会的にも大変意義深いものである．