A solvation-free-energy functional: A reference-modified density functional formulation

作者：Sumi Tomonari^*; Mitsutake Ayori; Maruyama Yutaka

来源：Journal of Computational Chemistry, 2015, 36(18): 1359-1369.

DOI：10.1002/jcc.23942

• salvation-free-energy
• classical density functional theory
• 3D-RISM theory
• water
• amino acid side-chain
• chignolin

The three-dimensional reference interaction site model (3D-RISM) theory, which is one of the most applicable integral equation theories for molecular liquids, overestimates the absolute values of solvation-free-energy (SFE) for large solute molecules in water. To improve the free-energy density functional for the SFE of solute molecules, we propose a reference-modified density functional theory (RMDFT) that is a general theoretical approach to construct the free-energy density functional systematically. In the RMDFT formulation, hard-sphere (HS) fluids are introduced as the reference system instead of an ideal polyatomic molecular gas, which has been regarded as the appropriate reference system of the interaction-site-model density functional theory for polyatomic molecular fluids. We show that using RMDFT with a reference HS system can significantly improve the absolute values of the SFE for a set of neutral amino acid side-chain analogues as well as for 504 small organic molecules.

• 出版日期2015-7-5