### Abstract

Molecular dynamics (MD) calculation has been carried out for a dilute aqueous solution of tert-butyl alcohol (TBA) at 298.15 K and with experimental density value by the use of constant temperature technique developed previously. The total number of molecule is 216, seven of which are TBA. The mole fraction of TBA is thus 0.032. For water-water and TBA-water interactions, the MCY (Matsuoka-Clementi-Yoshimine) potential and previously reported potential determined by MO calculation are used. A new potential for TBA-TBA is determined by ab initio LCAO SCF calculations for more than 500 different configurations with an STO-3G basis set and subsequent multiparameter fitting of the MO data to a 12-6-3-1 type potential energy function. The MD calculation is extended up to 84 000 time steps (26 ps) and final 60 000 time steps are used to calculate both static and dynamic properties of the system. Both hydrophobic hydration and interaction due to TBA molecules are proved to be stronger than those of methanol studied previously. Structural promotion of water is clearly observed in radial distribution functions and trajectories of each molecule. The configuration and trajectory of all the molecules in solution indicate clearly the association of TBA molecules. It is also found from pair interaction distribution functions that no hydrogen bonding interaction occurs between two TBA molecules. The self-diffusion coefficient of water in the solution is appreciably smaller than that in pure water.

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

Pages (from-to) | 4065-4073 |

Number of pages | 9 |

Journal | The Journal of Chemical Physics |

Volume | 81 |

Issue number | 9 |

Publication status | Published - 1984 |

Externally published | Yes |

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### ASJC Scopus subject areas

- Atomic and Molecular Physics, and Optics

### Cite this

*The Journal of Chemical Physics*,

*81*(9), 4065-4073.

**Computer experiments on aqueous solutions. VI. Potential energy function for tert-butyl alcohol dimer and molecular dynamics calculation of 3 mol % aqueous solution of tert-butyl alcohol.** / Tanaka, Hideki; Nakanishi, Koichiro; Touhara, Hidekazu.

Research output: Contribution to journal › Article

*The Journal of Chemical Physics*, vol. 81, no. 9, pp. 4065-4073.

}

TY - JOUR

T1 - Computer experiments on aqueous solutions. VI. Potential energy function for tert-butyl alcohol dimer and molecular dynamics calculation of 3 mol % aqueous solution of tert-butyl alcohol

AU - Tanaka, Hideki

AU - Nakanishi, Koichiro

AU - Touhara, Hidekazu

PY - 1984

Y1 - 1984

N2 - Molecular dynamics (MD) calculation has been carried out for a dilute aqueous solution of tert-butyl alcohol (TBA) at 298.15 K and with experimental density value by the use of constant temperature technique developed previously. The total number of molecule is 216, seven of which are TBA. The mole fraction of TBA is thus 0.032. For water-water and TBA-water interactions, the MCY (Matsuoka-Clementi-Yoshimine) potential and previously reported potential determined by MO calculation are used. A new potential for TBA-TBA is determined by ab initio LCAO SCF calculations for more than 500 different configurations with an STO-3G basis set and subsequent multiparameter fitting of the MO data to a 12-6-3-1 type potential energy function. The MD calculation is extended up to 84 000 time steps (26 ps) and final 60 000 time steps are used to calculate both static and dynamic properties of the system. Both hydrophobic hydration and interaction due to TBA molecules are proved to be stronger than those of methanol studied previously. Structural promotion of water is clearly observed in radial distribution functions and trajectories of each molecule. The configuration and trajectory of all the molecules in solution indicate clearly the association of TBA molecules. It is also found from pair interaction distribution functions that no hydrogen bonding interaction occurs between two TBA molecules. The self-diffusion coefficient of water in the solution is appreciably smaller than that in pure water.

AB - Molecular dynamics (MD) calculation has been carried out for a dilute aqueous solution of tert-butyl alcohol (TBA) at 298.15 K and with experimental density value by the use of constant temperature technique developed previously. The total number of molecule is 216, seven of which are TBA. The mole fraction of TBA is thus 0.032. For water-water and TBA-water interactions, the MCY (Matsuoka-Clementi-Yoshimine) potential and previously reported potential determined by MO calculation are used. A new potential for TBA-TBA is determined by ab initio LCAO SCF calculations for more than 500 different configurations with an STO-3G basis set and subsequent multiparameter fitting of the MO data to a 12-6-3-1 type potential energy function. The MD calculation is extended up to 84 000 time steps (26 ps) and final 60 000 time steps are used to calculate both static and dynamic properties of the system. Both hydrophobic hydration and interaction due to TBA molecules are proved to be stronger than those of methanol studied previously. Structural promotion of water is clearly observed in radial distribution functions and trajectories of each molecule. The configuration and trajectory of all the molecules in solution indicate clearly the association of TBA molecules. It is also found from pair interaction distribution functions that no hydrogen bonding interaction occurs between two TBA molecules. The self-diffusion coefficient of water in the solution is appreciably smaller than that in pure water.

UR - http://www.scopus.com/inward/record.url?scp=22244440342&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=22244440342&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:22244440342

VL - 81

SP - 4065

EP - 4073

JO - Journal of Chemical Physics

JF - Journal of Chemical Physics

SN - 0021-9606

IS - 9

ER -