Acta Phys. -Chim. Sin. ›› 2008, Vol. 24 ›› Issue (11): 2053-2058.doi: 10.3866/PKU.WHXB20081120

• ARTICLE • Previous Articles     Next Articles

Reaction Mechanisms of HCHO+X(X=F, Cl, Br)

LI Xiao-Yan; ZENG Yan-Li; MENG Ling-Peng; ZHENG Shi-Jun   

  1. Institute of Computational Quantum Chemistry, College of Chemistry and Material Science, Hebei Normal University, Shijiazhuang 050016, P. R. China
  • Received:2008-05-06 Revised:2008-07-21 Published:2008-11-10
  • Contact: ZHENG Shi-Jun

Abstract: The reactions of HCHO+X (X=F, Cl, Br) were studied at CCSD/6-311++G(d,p)//B3LYP/6-311++G (d,p) level. The computational results show that the reaction channel of halogen atom X (X=F, Cl, Br) which gains H atom of the HCHOto get HCO+HX(X=F, Cl, Br) is the main reaction channel. Except this reaction channel, a stable complex forms firstly, then the complex via two channels to get the products, one is that the halogen atom gains a hydrogen from HCHO to form HCO+HX(X=F, Cl, Br) and the other is that the complex decomposes directly to H and XCHO (X=F, Cl, Br). The first channel is the main channel and the HCO+HX(X=F, Cl, Br) are the main products. Furthermore, because the energy barriers of the three reactions are low, these reactions could occur easily. The topological analysis of electron density shows that there is a T-shape structure transition state (STS) in the channel (b) of HCHO+X reaction, the STS appears later than the energy transition state (ETS). And the STS appears later and later in the sequence of F, Cl, Br.

Key words: Air pollution, HCHO, Topological analysis of electron density, T-shape structure transition state