A)A molecule which possesses an inversion center is said to be centrosymmetric. We have seen that IR and Raman spectroscopy can be used to distinguish between alternative structures of molecules. If one is considering two possible structures of a molecule, one of which is centrosymmetric and one of which is not (for example, a molecule with formula ML4 could be square-planar or tetrahedral), the following rule is useful. In a centrosymmetric molecule, a given vibrational mode cannot be active in BOTH the IR and Raman spectrum, while in a non-centrosymmetric molecule, there is no such exclusion. Look at the character tables for a number of point groups and justify this rule.

A)A molecule which possesses an inversion center is said to be centrosymmetric. We have seen that IR and Raman spectroscopy can be used to distinguish between alternative structures of molecules. If one is considering two possible structures of a molecule, one of which is centrosymmetric and one of which is not (for example, a molecule with formula ML4 could be square-planar or tetrahedral), the following rule is useful. In a centrosymmetric molecule, a given vibrational mode cannot be active in BOTH the IR and Raman spectrum, while in a non-centrosymmetric molecule, there is no such exclusion. Look at the character tables for a number of point groups and justify this rule.

Organic Chemistry: A Guided Inquiry

2nd Edition

ISBN:9780618974122

Author:Andrei Straumanis

Publisher:Andrei Straumanis

ChapterL3: Carbon (13c) Nmr Spectroscopy

Section: Chapter Questions

Problem 1E

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