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An ab initio and molecular mechanical investigation of ureas and amide derivatives

✍ Scribed by Maria Kontoyianni; J. Phillip Bowen

Publisher: John Wiley and Sons
Year: 1992
Tongue: English
Weight: 690 KB
Volume: 13
Category: Article
ISSN: 0192-8651
DOI: 10.1002/jcc.540130516

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✦ Synopsis

A b initio molecular orbital theory with the 6-31G* basis set has been used to investigate the geometries and preferred conformations for urea, derivatives of urea, and a few complicated amide derivatives. The results from the ab initio calculations provide insight into the gas-phase rotational barrier about the C-N bond and have been used to generate parameters for the MM2(87) molecular mechanics program. When applicable, theoretical structures are compared with corresponding previously reported experimental geometries. Urea is predicted to be nonplanar with pyramidal amino groups.

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