Antimony sulfide is the chemical compound with the formula Sb2S3 which crystallizes in an orthorhombic space group. Sb2S3 shares striking structural and physical similarities with topological insulator Sb2Te3. The orthorhombic phase of Sb2S3 belongs to the space group Pnma (number:62) Recently, Sb2S3 has been shown to exhibit topological state transition under pressure . Sb2S3 crystals exhibit optical band gap at 1.7 -1.8 eV  while optical and electronic properties in the monolayer form remain unknown.
Sb2S3 crystals measure ~0.5 cm or larger in size, rated at 99.9998% purity, and exhibit strong and sharp Raman signal, ideal environmental stability, and high crystalline order. Crystals are synthesized through flux zone technique to high high crystallinity and enable exfoliation.