Accession Number : AD0612486

Title :   SPIN-ECHO NMR STUDIES OF CHEMICAL EXCHANGE. IV. INTRAMOLECULAR EXCHANGE OF A COUPLED AB SYSTEM,

Corporate Author : ILLINOIS UNIV URBANA NOYES CHEMICAL LAB

Personal Author(s) : Allerhand,Adam ; gutowsky,H. S.

Report Date : 14 FEB 1965

Pagination or Media Count : 37

Abstract : A mathematical and experimental study of the spin echo amplitudes in a Carr-Purcell train of echoes is reported for a coupled AB system undergoing intramolecular exchange. The density matrix approach was used to derive a set of four coupled recursion relations for the amplitudes of successive echoes. A program was written to investigate the properties of the system numerically with a high speed computer. Predictions were verified by F(19) spin echo experiments at 16.70 and 25.27 Mc/sec on 1,1-difluorocyclohexane in which axial and equatorial fluorines are interchanged by the chair-chair isomerization.

Descriptors :   (*EXCHANGE REACTIONS, NUCLEAR MAGNETIC RESONANCE), (*NUCLEAR MAGNETIC RESONANCE, EXCHANGE REACTIONS), (*HALOGENATED HYDROCARBONS, EXCHANGE REACTIONS), FLUORIDES, CYCLOHEXANES, REACTION KINETICS, MOLECULAR ISOMERISM, ABSORPTION SPECTRA, NUCLEAR SPINS

Distribution Statement : APPROVED FOR PUBLIC RELEASE