4-Phenyl-1,2,4-triazaspiro[4.4] non-1-ene-3-thione

In the title compound, C12H13N3S, the 4,5-dihydro-3H-1,2,4triazole system is nearly planar [maximum deviation = 0.014 (2) angstrom], while the cyclopentane ring adopts a half-chair conformation. The dihedral angle between the mean plane of the 4,5-dihydro-3H-1,2,4-triazole-3-thione ring and the phenyl ring is 85.49 (14)degrees, with the S atom 0.046 (1) angstrom out of the former plane. The crystal structure is stabilized only by van der Waals interactions. The investigated crystal was found to be a non-merohedral two-component twin by a 180 degrees rotation about c*, with a refined value of the minor twin fraction of 0.12203 (18)