✦ LIBER ✦

Calculations of the 13C nuclear screening tensors for coumarin and some methoxycoumarins

✍ Scribed by G. I. Grigor; G. A. Webb

Publisher: John Wiley and Sons
Year: 1977
Tongue: English
Weight: 250 KB
Volume: 9
Category: Article
ISSN: 0749-1581
DOI: 10.1002/mrc.1270090806

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✦ Synopsis

Abstract

INDO calculations are reported of the ^13^C nuclear screening tensors in coumarin and some of its methoxy derivatives. Calculations based upon a linear combination of gauge dependent atomic orbitals and those using an uncoupled Hartree–Fock approach are described. Comparison with the results of less sophisticated calculations shows that changes in the excitation energies, bond orders and the 〈r^−3^〉~2p~ term are together responsible for determining the ^13^C chemical shifts.

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