Modification of molecular packing: crystal structures and magnetic properties of monomeric and dimeric difluorophenyl-1,2,3,5-dithiadiazolyl radicals

Two dithiadiazolyl radicals of formula [F2C6H3&z.ub1s;CNSSN&z.ub1e;] &z.rad; were prepared and characterised by X-ray crystallography; in the solid state the 2′,3′-difluoro isomer forms discrete twisted dimers through a spin-paired singly occupied–singly occupied molecular orbital interaction with an intra-dimer S · · ·   S distance of 3.020(4) Å, whereas the 2′,5′-isomer is composed of uniform stacks with unexpectedly long intra-stack S · · ·   S contacts [3.544(3) Å].