摘要
Ab initio study of the reactions ofn-heptyl radicals（1-C7H15, 2-C7H15, 3-C7H15, and 4-C7H15） with metha- nol was conducted over the temperature range of 300--1500 K. Transition states for the reaction channels producing CTH15OH, CH3, C7H15OCH3, H, C7H16, CH2OH and CH30 were identified and the geometries of all stationary points were calculated at BB1K/MG3S level of theory. The potential barrier heights of the corresponding transition states were predicted by the CBS-QB3//BB1K and G4//BB1K methods, indicating that the eight H-abstraction channels are more kinetically favorable than the channels where OH transfers from CH3OH to C7H15 and where the CTHIsOCH3＋H products are given. Tile rate constants of H-abstraction channels were calculated with TST and TST/Eck. Both the forward and reverse rate constants have positive temperature dependence and the ttmneling effect is only important at the temperature lower than 700 K. For the reactions of H-atom abstraction from methyl in CH3OH by n-heptyl, a reverse and the corresponding forward rate constant are roughly equal. For the reactions of H-atom abstraction from OH in CH3OH by n-heptyl, a reverse rate constant is larger by several orders of magnitude thin1 the corresponding forward one.
Ab initio study of the reactions ofn-heptyl radicals（1-C7H15, 2-C7H15, 3-C7H15, and 4-C7H15） with metha- nol was conducted over the temperature range of 300--1500 K. Transition states for the reaction channels producing CTH15OH, CH3, C7H15OCH3, H, C7H16, CH2OH and CH30 were identified and the geometries of all stationary points were calculated at BB1K/MG3S level of theory. The potential barrier heights of the corresponding transition states were predicted by the CBS-QB3//BB1K and G4//BB1K methods, indicating that the eight H-abstraction channels are more kinetically favorable than the channels where OH transfers from CH3OH to C7H15 and where the CTHIsOCH3＋H products are given. Tile rate constants of H-abstraction channels were calculated with TST and TST/Eck. Both the forward and reverse rate constants have positive temperature dependence and the ttmneling effect is only important at the temperature lower than 700 K. For the reactions of H-atom abstraction from methyl in CH3OH by n-heptyl, a reverse and the corresponding forward rate constant are roughly equal. For the reactions of H-atom abstraction from OH in CH3OH by n-heptyl, a reverse rate constant is larger by several orders of magnitude thin1 the corresponding forward one.
基金
Supported by the National Natural Science Foundation of China（No.51576139）.
