A METHOD FOR OPTIMIZING THE STUDY OF SLOW CHEMICAL-EXCHANGE BY NMR SPIN-RELAXATION MEASUREMENTS - APPLICATION TO TRIPODAL CARBONYL ROTATION IN A METAL-COMPLEX

被引:51
作者
BAIN, AD
CRAMER, JA
机构
[1] Department of Chemistry, McMaster University, Hamilton, ON, L8S 4M1
关键词
D O I
10.1006/jmra.1993.1156
中图分类号
O64 [物理化学(理论化学)、化学物理学]; O56 [分子物理学、原子物理学];
学科分类号
070203 ; 070304 ; 081704 ; 1406 ;
摘要
A new general method for measurement of chemical exchange rates which are slow on the NMR time scale is presented. Spin-relaxation measurements have long been used to study slow exchange. With modern spectrometric methods, it is possible to create almost any initial nonequilibrium state from which the system relaxes. This paper presents a criterion for choosing the "best" initial state to probe a given relaxation pathway. The basic theory is developed and measurements of a carbonyl scrambling process in an organometailic compound, Ru2(CO)6(μ2P Ph2)(μ2η2-CCBut), are presented. It is found that the threefold scrambling of the carbonyls at each ruthenium appears to be a concerted process. © 1993 by Academic Press, Inc.
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页码:217 / 222
页数:6
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