Ab initio MO studies on protonation mechanism of ethylene over catalyst HZSM-5

Abstract

Four calculation models (I–IV) were proposed for studying the protonation mechanism of ethylene over catalyst HZSM-5. Ab initio SCF-MO calculations were carried out at the STO-3G basis set level. From the calculation results of geometry optimization and Mulliken population of these models, it has been shown that the cis-four-centered reaction mechanism (model I) is the most reasonable one, while the vertical complex reaction mechanism (model II) is of no effect, and models III and IV are possible for the terminal radical absorption.