not sure exactly what is causing the peak to converge at high temperature. I'm guessing that for digmagnetic moment to be induced the plane must be perpendicular to the appled magnetic field but at high temperature the annulene rotate too fast that the plane can never really perpendicular to the applied magnetic field? 9.The variation with temperature of the 1H chemical shifts of (18]annulene insolution is as shown below. Comment as fully as possible on this behaviour and on thelinewidths in the temperature ranges -60 °C to +20 °C and +70 °C to 110 °C. (From 1990Advanced Paper.)935-2-30-60-20+20+60TrCSippm

Answered: Image /qna-images/answer/bc1a143b-1bd2-427a-8e9d-3f96a5c0c79a.jpg

9. The variation with temperature of the H chemical shifts of [18]annulene in solution is as shown below. Comment as fully as possible on this behaviour and on the linewidths in the temperature ranges -60 °C to +20 °C and +70 °C to 110 °C. (From 1990 Advanced Paper.)

9. The variation with temperature of the H chemical shifts of [18]annulene in solution is as shown below. Comment as fully as possible on this behaviour and on the linewidths in the temperature ranges -60 °C to +20 °C and +70 °C to 110 °C. (From 1990 Advanced Paper.)

Chemistry for Engineering Students

3rd Edition

ISBN:9781285199023

Author:Lawrence S. Brown, Tom Holme

Publisher:Lawrence S. Brown, Tom Holme

Chapter5: Gases

Section: Chapter Questions

Problem 5.23PAE

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not sure exactly what is causing the peak to converge at high temperature. I'm guessing that for digmagnetic moment to be induced the plane must be perpendicular to the appled magnetic field but at high temperature the annulene rotate too fast that the plane can never really perpendicular to the applied magnetic field?

9.
The variation with temperature of the 1H chemical shifts of (18]annulene in
solution is as shown below. Comment as fully as possible on this behaviour and on the
linewidths in the temperature ranges -60 °C to +20 °C and +70 °C to 110 °C. (From 1990
Advanced Paper.)
93
5-2
-30
-60
-20
+20
+60
TrC
Sippm

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