### Abstract

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.

Original language | English |
---|---|

Pages (from-to) | 1359-1369 |

Number of pages | 11 |

Journal | Journal of Computational Chemistry |

Volume | 36 |

Issue number | 18 |

DOIs | |

Publication status | Published - 2015 Jul 1 |

### Fingerprint

### Keywords

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

### ASJC Scopus subject areas

- Chemistry(all)
- Computational Mathematics

### Cite this

*Journal of Computational Chemistry*,

*36*(18), 1359-1369. https://doi.org/10.1002/jcc.23942

**A solvation-free-energy functional : A reference-modified density functional formulation.** / Sumi, Tomonari; Mitsutake, Ayori; Maruyama, Yutaka.

Research output: Contribution to journal › Article

*Journal of Computational Chemistry*, vol. 36, no. 18, pp. 1359-1369. https://doi.org/10.1002/jcc.23942

}

TY - JOUR

T1 - A solvation-free-energy functional

T2 - A reference-modified density functional formulation

AU - Sumi, Tomonari

AU - Mitsutake, Ayori

AU - Maruyama, Yutaka

PY - 2015/7/1

Y1 - 2015/7/1

N2 - 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.

AB - 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.

KW - 3D-RISM theory

KW - amino acid side-chain

KW - chignolin

KW - classical density functional theory

KW - salvation-free-energy

KW - water

UR - http://www.scopus.com/inward/record.url?scp=84931272634&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84931272634&partnerID=8YFLogxK

U2 - 10.1002/jcc.23942

DO - 10.1002/jcc.23942

M3 - Article

VL - 36

SP - 1359

EP - 1369

JO - Journal of Computational Chemistry

JF - Journal of Computational Chemistry

SN - 0192-8651

IS - 18

ER -