Naphthaceno[5,6-cd]-1,2-dithiole, C18H10S2

C18H10S2,M=290.34, monoclinic,P21,a=20.556(5),b=15.843(3),c=3.963(1) A,β=92.79(2)° at 18°C,Z=4,D x =1.496 g cm−3,μ(Cu Kα)=3.53 mm−1. Full-matrix least-squares refinement resulted in a final conventionalR value of 0.036 for 2030 observed reflections. The average C-S bond distance is 1.747(16) A, the S-S bond length is 2.074(1) A. The torsion angles at the disulfide group are close to zero, at 3.5 and 0.8°. The carbon frameworks are nearly planar, and closely approximate symmetrymmm. Bond distances are comparable with those in related molecules.