## 摘要

The absolute rate constants for the C_{6}H_{5} + C_{6}H_{6} and C_{6}D_{6} reactions have been measured by cavity ringdown spectrometry at temperatures between 298 and 495 K at a constant 40 Torr Ar pressure. The new results, which reveal no detectable kinetic isotope effect, can be represented by the Arrhenius equation, k_{1} = 10^{(11.9±91±0.13)} exp[-(2102 ± 106)/T] cm^{3}/(mol s). Our low-temperature data for the addition/stabilization process, C_{6}H_{5} + C_{6}H_{6} → C_{12}H_{11}, can be correlated with those obtained in a low-pressure, high-temperature Knudsen cell study for the addition/displacement reaction, C_{6}H_{5} + C_{6}H_{6} → C_{12}H_{10} + H, by the RRKM theory using the molecular and transition-state parameters computed at the B3LYP/6-311G(d,p) level of theory. Combination of these two sets of data gives k_{1} = 10^{(11.98±0.03)} exp[-(2168 ±34)/T] cm^{3}(mol s) covering the temperature range 298-1330 K. The RRKM theory also correlates satisfactorily the forward reaction data with the high-temperature shock-tube result for the reverse H-for-C_{6}H_{5} substitution process with 2.7 and 4.7 kcal/mol barriers for the entrance (C_{6}H_{5} + C_{6}H_{6}) and reverse (H + C_{12}H_{10}) reactions, respectively. For modeling applications, we have calculated the forward reaction rate constants for the formation of the two competing products, H + C_{12}H_{10} and C_{12}H_{11}, at several pressures covering 300 K < T < 2500 K.

原文 | English |
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頁（從 - 到） | 9036-9041 |

頁數 | 6 |

期刊 | Journal of Physical Chemistry A |

卷 | 103 |

發行號 | 45 |

DOIs | |

出版狀態 | Published - 11 十一月 1999 |