THE MICROWAVE-SPECTRUM OF N-BUTYRALDEHYDE OXIME

The microwave spectrum of n-butyraldehyde oxime was observed in the fr equency region 26.5-40 GHz. Four rotational conformers were found to e xist in the gas phase; among these, two conformers belonged to the (E) -geometrical isomer and the other two to the (Z)-geometrical isomer. T he microwave spectrum attributed to one of these two rotational confor mers of (E)-butyraldehyde oxime was analyzed, and its rotational const ants for the ground vibrational state were determined: A = 15883(379), B = 1269.97(1), C = 1251.60(1) MHz. The conformational structure of t he molecule is discussed, referring to the rotational constants obtain ed and the ab initio molecular orbital calculation. (C) 1998 Academic Press.