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1H NMR study of internal motions and quantum rotational tunneling in (CH3)4NGeCl3

✍ Scribed by K. J. Mallikarjunaiah; K. Jugeshwar Singh; K. P. Ramesh; R. Damle

Publisher
John Wiley and Sons
Year
2008
Tongue
English
Weight
143 KB
Volume
46
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

(CH~3~)~4~NGeCl~3~ is prepared, characterized and studied using ^1^H NMR spin lattice relaxation time and second moment to understand the internal motions and quantum rotational tunneling. Proton second moment is measured at 7 MHz as function of temperature in the range 300–77 K and spin lattice relaxation time (T~1~) is measured at two Larmor frequencies, as a function of temperature in the range 270–17 K employing a homemade wide‐line/pulsed NMR spectrometers. T~1~ data are analyzed in two temperature regions using relevant theoretical models. The relaxation in the higher temperatures (270–115 K) is attributed to the hindered reorientations of symmetric groups (CH~3~ and (CH~3~)~4~N). Broad asymmetric T~1~ minima observed below 115 K down to 17 K are attributed to quantum rotational tunneling of the inequivalent methyl groups. Copyright © 2007 John Wiley & Sons, Ltd.

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