### Abstract

The use of importance sampling as a variance reduction technique is applied to the direct Monte Carlo quasi-classical trajectory (MCQT) calculation of bimolecular gas phase rate constants. A general importance sampling function for the collision energy having a single (integer) parameter which characterizes the distribution of collision energies to be sampled is proposed and used in calculations of rate constants for three chemical reactions [F + H_{2}, Cl + H_{2}, and O(^{3}P) + H_{2}] at several temperatures. Results are compared with regard to accuracy and efficiency with rate constants obtained directly or indirectly using other MCQT approaches and the same potential energy surfaces. The importance sampling calculations are found to be more efficient over the entire range of reactivity studied, and provide statistically valid estimates of the errors in the computed rate constants.

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

Pages (from-to) | 79-88 |

Number of pages | 10 |

Journal | Journal of Physical Chemistry |

Volume | 83 |

Issue number | 1 |

Publication status | Published - 1979 |

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### ASJC Scopus subject areas

- Physical and Theoretical Chemistry

### Cite this

*Journal of Physical Chemistry*,

*83*(1), 79-88.

**Rate constants from Monte Carlo quasi-classical trajectory calculations. A procedure for importance sampling.** / Muckerman, James; Faist, M. B.

Research output: Contribution to journal › Article

*Journal of Physical Chemistry*, vol. 83, no. 1, pp. 79-88.

}

TY - JOUR

T1 - Rate constants from Monte Carlo quasi-classical trajectory calculations. A procedure for importance sampling

AU - Muckerman, James

AU - Faist, M. B.

PY - 1979

Y1 - 1979

N2 - The use of importance sampling as a variance reduction technique is applied to the direct Monte Carlo quasi-classical trajectory (MCQT) calculation of bimolecular gas phase rate constants. A general importance sampling function for the collision energy having a single (integer) parameter which characterizes the distribution of collision energies to be sampled is proposed and used in calculations of rate constants for three chemical reactions [F + H2, Cl + H2, and O(3P) + H2] at several temperatures. Results are compared with regard to accuracy and efficiency with rate constants obtained directly or indirectly using other MCQT approaches and the same potential energy surfaces. The importance sampling calculations are found to be more efficient over the entire range of reactivity studied, and provide statistically valid estimates of the errors in the computed rate constants.

AB - The use of importance sampling as a variance reduction technique is applied to the direct Monte Carlo quasi-classical trajectory (MCQT) calculation of bimolecular gas phase rate constants. A general importance sampling function for the collision energy having a single (integer) parameter which characterizes the distribution of collision energies to be sampled is proposed and used in calculations of rate constants for three chemical reactions [F + H2, Cl + H2, and O(3P) + H2] at several temperatures. Results are compared with regard to accuracy and efficiency with rate constants obtained directly or indirectly using other MCQT approaches and the same potential energy surfaces. The importance sampling calculations are found to be more efficient over the entire range of reactivity studied, and provide statistically valid estimates of the errors in the computed rate constants.

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UR - http://www.scopus.com/inward/citedby.url?scp=0040348452&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0040348452

VL - 83

SP - 79

EP - 88

JO - Journal of Physical Chemistry

JF - Journal of Physical Chemistry

SN - 0022-3654

IS - 1

ER -