An X-ray crystallographic analysis of a 1S′ derivative revealed the presence of intramolecular S•••S chalcogen bonding interactions in both ZZ and EZ isomers. In the ZZ isomer, the S•••S distances (approximately 3.04 Å) were shorter than the sum of the van der Waals radii, with near-ideal C-S•••S angles of 171°, strongly supporting the presence of chalcogen bonding. Comprehensive conformer searches and DFT calculations not only validated the higher stability of the ZZ isomer in 1S but also provided calculated isomer distributions that closely matched the experimental values.