Eric A. Arsenault

Iodine: many electrons and much to discuss...THE Nuclear quadrupole coupling, nuclear spin-rotation, conformational analysis, and structural determination of 2-Iodobutane

The rotational spectrum of 2-iodobutane (sec-butyl-iodide) has been collected from 5.5-16.5 GHz using jet-pulsed Fourier transform microwave spectroscopy on both broadbanda and Balle-Flygare cavityb instruments. Transitions belonging to three unique conformers were observed, namley the gauche-, anti-, and gauche′species. All four C isotopologues of the gauche-2-iodobutane were observed. The complete nuclear quadrupole coupling tensor of iodine has been determined for all conformers and C isotopologues. A comparison between these nuclear quadrupole coupling tensors and those of similar iodine-containing molecules will be presented. Changes in the quadrupole coupling of iodine upon isotopic substitution will also be discussed. Additionally, isotopic substitution in conjunction with ab initio calculations allowed for both an rs and r0 structural analysis of gauche-2-iodobutane.

HYDROGEN BONDING IN 4-AMINOPHENYL ETHANOL: A COMBINED IR-UV DOUBLE RESONANCE AND MICROWAVE STUDY

H2N OH Both amine and hydroxyl functional groups are present in 4-aminophenyl ethanol (4-AE), and each functional group can form hydrogen bonds with carboxylic acids, such as formic acid and acetic acid. Predicting the structures of such complexes involving 4-AE is rather complex, given the many possible conformations and their similar (and method and basis-dependent) energies. In particular, the carboxyl group, -COOH, can act as both as a hydrogen bond donor or acceptor, or both at once.