摘要
用流动放电-化学发光技术测定了O(~3p)原子与乙醚和异丙醚总包二级反应速率常数。反应速率常数与温度关系可表达为k_1=(1.91±0.70)×10^(-11)exp[-(2.14±0.16)kcal·mol^(-1)/RT]·cm^3·molec.^(-1)·s^(-1) [O(~3p)+乙醚] k_2=(3.25±0.80)×10^(-11)exp[-(2.57±0.20)kcal·mol^(-1)/RT]·cm^3·molec.^(-1)·s^(-1) [O(~3p)+异丙醚] 还讨论了醚分子中氧原子对α-位C—H键能及其反应活化能的影响。结果表明,氧原子使α位C—H键能减弱而降低了反应活化能。
This paper presents the measurements of rate constants for reactions of O(~3p) atoms with ether and isopropyl ether molecules by using discharge flow-chemiluminescence technique. The Arrhenius parameters are derived. The rate constants over temperature range 313—463K for these reactions can be expressed as follows:
k_1=(1.91±0.70)×10^(-11)exp(-(2.14±0.16)kcal·tool.^(-1)/RT)cm^3·molec. ^(-1)s^(-1) (for O(~3p)+ether)
k_2=(3.25±0.80)×10^(-11)exp(-(2.57±0.20)kcal·tool.^(-1)/RT)cm^3molec. ^(-1)·s^(-1) (for O(~3p)+ isopropyl ether)
The discussion of effects of oxygen atom in ehter molecules on the C—H bond strength as well as the activation energy of reaction of the C—H bond is presented. It is found that the induction of oxygen atoms in ether molecules reduces the strength of the C—H bond as well as the activation energy which is in α position of oxygen atoms.
