MECHANISTIC STUDY OF THE PHYSICAL QUENCHING OF LI-STAR BY N2 - COMPARISON OF DIABATIC AND VB POTENTIAL-ENERGY SURFACES

被引：15

作者：

SEVIN, A ^{[1
]}

GIESSNERPRETTRE, C ^{[1
]}

HIBERTY, PC ^{[1
]}

NOIZET, E ^{[1
]}

机构：

[1] UNIV PARIS 11,CHIM THEOR LAB,F-91405 ORSAY,FRANCE

来源：

JOURNAL OF PHYSICAL CHEMISTRY | 1991年 / 95卷 / 22期

关键词：

D O I：

10.1021/j100175a032

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The mechanism of low-lying exciplex formation in the Li (excited) + N2 (ground state) system has been studied by means of ab initio calculations of adiabatic and diabatic potential surfaces. The diabatic states have been obtained by two different techniques: direct valence bond calculations and diabatization of MO-CI wavefunctions by Lorquet's method. Both approaches exhibit a strong analogy and evidence the same dominant trend: the attractive ionic charge transfer Li+/N2- and the neutral Li./N2 diabatic surfaces cross at short distances, thus leading, through avoided crossing, to a strong adiabatic exciplex of mixed neutral and ionic nature. This exciplex further crosses the ground state, thus leading to the quenching process. The role of the ionic diabatic state is found to be predominant, in agreement with the mechanism proposed by Nikitin.

引用

页码：8580 / 8584

页数：5

共 22 条

[1]

Bjerre A., 1967, CHEM PHYS LETT, V1, P179

[2] THEORY OF FREE-RADICAL REACTIONS [J].