Spin-density distribution in the new molecular magnet p-O2N•C6F4•CNSSN

Knowledge of the spin-density distribution in the dithiadiazolyl radical ring (DTDA) constitutes a major step towards the understanding of the magnetic and electronic properties of the rich magnetism of DTDA derivatives. The O2N-center-dot-C6F4CNSSN radical was chosen as the most favourable CNSSN derivative to study the spin distribution in this kind of free radicals by polarised-neutron diffraction. Spin-density maps obtained for the O2N C6F4CNSSN. radical show that almost all the spin density is localised on the sulphur and nitrogen atoms of the CNSSN. ring. A small negative spin density on the carbon atom of the CNSSN. ring and a negligible spin density over the rest of the radical are observed, in good agreement with ab initio calculations. (C) 2003 Elsevier Science B.V. All rights reserved.