The Rotational Zeeman Effect of Thiazole and Isothiazole

Abstract

The rotational Zeeman effect of low J rotational transitions (J ≦ 3) has been investigated for Thiazole and Isothiazole. The measured susceptibilities are compared to those calculated within the model of localized (atomic) susceptibilities, and nonlocal contributions to the susceptibility component perpendicular to the ring are obtained. These nonlocal susceptibilities, if compared to those of a set of related compounds appear to correlate to the “aromatic character” as determined by chemical reactivity. Five or six membered rings with Χ ⊥ nonlocal < - 30 · 10 -6 erg/G 2 mol show “aromatic reactions” while molecules with -20 · 10 -6 erg/G 2 < Χ ⊥ nonlocal show “olefinic reactions”.