A Spontaneous\nMagnetic Moment in an Organic Radical:\nSynthesis and Characterization of Benzodioxepinyl-1,3,2-dithiazolyl

The\nsynthesis of the 1,3,2-dithiazolyl radical (<b>1</b>)\nderived from 3,4-dihydro-2H-1,5-benzodioxepine is described. Crystals\nof <b>1</b> were grown by vacuum sublimation and adopt the orthorhombic\nspace group <i>Pbca</i>. DC SQUID magnetometry reveals Curie–Weiss\nbehavior for <i>T</i> > 20 K (<i>C</i> = 0.376\nemu K mol<sup>–1</sup> and θ = +5.7 K) consistent with\nlocal ferromagnetic interactions. The presence of weaker antiferromagnetic\ninteractions led to magnetic ordering as a canted antiferromagnet\n(T<sub>N</sub> = 3.8 K) with a small spontaneous moment (2.5 ×\n10<sup>–4</sup> Nβ) and a small coercivity (<i>ca</i>. 8 Oe) at 2 K. Magnetic ordering was reflected in a field dependence\nof the magnetic susceptibility below 3.8 K and a peak in the low temperature\nheat capacity data. A canting angle of 0.08° was estimated from <i>M</i> vs <i>H</i> data.