NC–(CF2)4–CNSSN˙ containing 1,2,3,5-dithiadiazolyl radical dimer exhibiting triplet excited states at low temperature and thermal hysteresis on melting–solidification: structural, spectroscopic, and magnetic characterization - Shuvaev, Konstantin V.; Decken, Andreas; Grein, Friedrich; Abedin, Tareque S. M.; Thompson, Laurence K.; Passmore, Jack (Dalton transactions : an international journal of inorganic chemistry, 2008)