## Abstract

The mechanism for ClO + NH_{2} has been investigated by ab initio molecular orbital and transition-state theory calculations. The species involved have been optimized at the B3LYP/6-311+G(3df,2p) level and their energies have been refined by single-point calculations with the modified Gaussian-2 method, G2M(CC2). Ten stable isomers have been located and a detailed potential energy diagram is provided. The rate constants and branching ratios for the low-lying energy channel products including HCl + HNO, Cl + NH_{2}O, and HOCl + ^{3}NH (X^{3}Σ^{-}) are calculated. The result shows that formation of HCl + HNO is dominant below 1000 K; over 1000 K, Cl + NH_{2}O products become dominant. However, the formation of HOCl + ^{3}NH (X^{3}Σ^{-}) is unimportant below 1500 K. The pressure-independent individual and total rate constants can be expressed as k_{1}(HCl + HNO) = 4.7 × 10^{-8}(T-^{1.08}) exp(^{-129}/_{T}), k_{2}(Cl + NH_{2}O) = 1.7 × 10^{-9}(T^{-0.62}) exp(^{-24}/_{T}), k_{3}(HOC1 + NH) = 4.8 × 10^{-29}(T^{5.11}) exp(^{-1035}/_{T}), and k_{total} = 5.0 × 10 ^{-9}(T^{-0.67}) exp(-^{1.2}/_{T}), respectively, with units of cm^{3} molecule^{-1} s^{-1}, in the temperature range of 200-2500 K.

Original language | English |
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Pages (from-to) | 3977-3983 |

Number of pages | 7 |

Journal | Journal of Physical Chemistry A |

Volume | 111 |

Issue number | 19 |

DOIs | |

State | Published - 17 May 2007 |