A review of infrared spectroscopy of proteins contains the following two statements: i) The C=O stretching vibration absorbs near 1650 cm-¹ ii) The N-H stretching vibration gives rise to the amide A band between 3310 and 3270 cm¹ The bond energy values for single bonds N-H and C-O are 386 kJ/mol and 380 kJ/mol respectively. a) Your colleague is asking you for a quantitative explanation on why the IR wavenumber (in cm¹) of the N-H stretching vibrations is about double of that for C=O stretching vibrations.

A review of infrared spectroscopy of proteins contains the following two statements: i) The C=O stretching vibration absorbs near 1650 cm-¹ ii) The N-H stretching vibration gives rise to the amide A band between 3310 and 3270 cm¹ The bond energy values for single bonds N-H and C-O are 386 kJ/mol and 380 kJ/mol respectively. a) Your colleague is asking you for a quantitative explanation on why the IR wavenumber (in cm¹) of the N-H stretching vibrations is about double of that for C=O stretching vibrations.

Principles of Instrumental Analysis

7th Edition

ISBN:9781305577213

Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Chapter16: An Introduction To Infrared Spectrometry

Section: Chapter Questions

Problem 16.16QAP

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