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The far infrared ͑FIR͒ spectra of various isotopic species of ethanol ͑-h 6 ,-d 1 , and-d 3 ͒ are analyzed from MP4͑͑SDQT͒ ab initio calculations using models in one and two dimensions. From the calculated frequencies and intensities, previous assignments of ethanol-h 6 and-d 1 bands are reviewed. The position of several combination bands are predicted. Ethanol shows two conformers, trans and gauche, and two interacting torsional modes. The torsional barriers have been calculated to be V 3 ͑trans͒ ϭ1226.7 cm Ϫ1 , V 3 ͑gauche͒ ϭ1296.3 cm Ϫ1 , V OH (␣ϭ62°)ϭ404.1 cm Ϫ1 , and V OH (␣ ϭ180°)ϭ423.3 cm Ϫ1. The flexible models in one and two dimensions yields the same OH torsional frequencies, whereas they differ in the methyl group state calculations. The fundamental bands of the ethanol-h 6 have been evaluated at 205.5 cm Ϫ1 ͑OH torsion͒ and 257.0 cm Ϫ1 ͑CH 3 torsion͒ and their corresponding intensities to be 18.650ϫ10 Ϫ4 and 0.662ϫ10 Ϫ4 .

The molecular structure of methyl formate is determined from ab initio calculations. The molecule presents two conformers (cis and trans) with a 5.3 kcal mol À1 difference in energy. In the most stable cis conformer, the carbonyl group eclipses the methyl group. The internal rotation barriers are V 3 (cis) ¼ 368 cm À1 and V 3 (trans) ¼ 26 cm À1 for the methyl group and V CO ¼ 4826 cm À1 for the CO group. The dependence of the spectroscopic parameters on the torsional motions is detailed. The rotational-torsional energy levels have been calculated variationally up to J ¼ 6 using a flexible model depending on the two torsional modes. Far-infrared frequencies and intensities are determined at room temperature. The rotational parameters have been computed to be A

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Sulfonamides obtained by reaction of 8‐aminoquinoline with benzenesulfonyl, toluene‐4‐sulfonyl and naphthalene‐2‐sulfonyl chlorides have been used to synthetize coordination compounds with ZnII with a ZnL2 composition. Determination of the crystal structures for the resulting complexes by X‐ray diffraction shows a distorted tetrahedral environment for the Zn2+ ions, sulfonamides acting as bidentate ligands through the nitrogen atoms from the sulfonamidate and quinoline groups. FT‐IR, 1H and 13C NMR and mass spectra of these compounds are also discussed.