The g and hyperfine tensor components of the thiopheno-1,3,2-dithiazolyl radical are computed by Neese's coupled-perturbed KohnSham hybrid density functional (UPBE0, UB1LYP) techniques. Their values are in very good agreement (within 1 ppt) with those determined experimentally. Furthermore, the one- and two-electron contributions to the g tensor are separated and analyzed. In comparison to the larger aug-cc-pVTZ basis, the EPR-II basis sets are found to give similar results and are approximately 50 times faster. Thus, the g and hyperfine tensors of this class of radicals are feasibly and accurately calculated in a reasonable amount of time without using post HF techniques. (c) 2005 Elsevier B.V. All rights reserved.