Theoretical Studies on the Unimolecular Decomposition of Ethylene Glycol

详细信息    查看全文

• 作者：Lili Ye ; Long Zhao ; Lidong Zhang ; Fei Qi
• 刊名：The Journal of Physical Chemistry A
• 出版年：2012
• 出版时间：January 12, 2012
• 年：2012
• 卷：116
• 期：1
• 页码：55-63
• 全文大小：507K
• 年卷期：v.116,no.1(January 12, 2012)
• ISSN：1520-5215

文摘

The unimolecular decomposition processes of ethylene glycol have been investigated with the QCISD(T) method with geometries optimized at the B3LYP/6-311++G(d,p) level. Among the decomposition channels identified, the H₂O-elimination channels have the lowest barriers, and the C鈥揅 bond dissociation is the lowest-energy dissociation channel among the barrierless reactions (the direct bond cleavage reactions). The temperature and pressure dependent rate constant calculations show that the H₂O-elimination reactions are predominant at low temperature, whereas at high temperature, the direct C鈥揅 bond dissociation reaction is dominant. At 1 atm, in the temperature range 500鈥?000 K, the calculated rate constant is expressed to be 7.63 脳 10⁴⁷T^鈥?0.38 exp(鈭?2262/T) for the channel CH₂OHCH₂OH 鈫?CH₂CHOH + H₂O, and 2.48 脳 10⁵¹T^鈥?1.58 exp(鈭?3593/T) for the channel CH₂OHCH₂OH 鈫?CH₃CHO + H₂O, whereas for the direct bond dissociation reaction CH₂OHCH₂OH 鈫?CH₂OH + CH₂OH the rate constant expression is 1.04 脳 10⁷¹T^鈥?6.16 exp(鈭?2414/T).