Modification of the solid state structures of dithiadiazolyl radicals: crystal structure of p-iodophenyl-1,2,3,5-dithiadiazolyl

The solid state structure of the 1,2,3,5-dithiadiazolyl p-IC6H4CNSSN (3) is described. The molecules associate in dimer pairs, across an inversion cen tre, in an unusual trans-cofacial manner. The separation between the hetero cyclic rings is 3.121 Angstrom. The intradimer sulfur contacts (3.696 Angst rom) are larger than those observed in dithiadiazolyls that associate in th e more usual cis-cofacial manner. Individual p-IC6H4CNSSN molecules are lin ked into zigzag chains through weak I ... S interactions (3.82 Angstrom); e ach half of a [p-IC6H4CNSSN](2) dimer is a member of separate chains that r un in opposite directions. (C) 2000 Elsevier Science Ltd All rights reserve d.