Showing papers by "Xiamen University published in 1981"
TL;DR: In this article, a model of active center for ammonia synthesis on iron catalysts is proposed, and the inclinedly-mounting model seems to give more effective coordination activation of N 2 ; it also gives better interpretation of the isotoplc exchange between 30 N 2 and 28 N 2.
Abstract: This work is an attempt to discuss the molecular catalysis of ammonia synthesis on iron catalysts. The following points are proposed: (1) A model of active center for this reaction and the ω 1 ,- μ 3 ', μ 3 (η 2 ) (or better denoted as ω 1 , ω 1 ,- μ 2 ', μ 3 (η 2 ) inclinedly-raounting mode of coordination activation of N 2 . Quantumchemical EHMO self-consistent charge calculations have been used to estimate the relative effectiveness for two modes of coordination activation of dinitrogen. The inclinedly-mounting model seems to give more effective coordination activation of N 2 ; it also gives better interpretation of the isotoplc exchange between 30 N 2 and 28 N 2 . (2) Activation of hydrogen is assumed to be due to a weak chemisorption with induced polarization at the vicinity of the exo-N of a coordinated N 2 ; with this modification to one of Temkin's original assumptions, extended kinetic equation proposed by Temkin (1963) can be derived, and the inversed kinetic isotopic effect of hydrogen observed experimentally can be readily explained. Other experimental facts are briefly discussed and correlated.
3 citations