The growth of SeS and SeSnS2 microcrystals by slow evaporation technique was established, respectively, from the solution of selenium sulfide (SeS2) and selenium sulfide (SeS2) and tin sulfide (SnS2) mixtures in CS2. Monoclinic and orthorhombic structures are evident for SeS and SeSnS2, respectively, with single-crystal X-ray diffraction (XRD) analysis. Powder-XRD analysis shows that the spectra due to SeS and SeSnS2 are found to be superimposed with their structural peaks. Elemental compositions are analyzed by energy dispersive X-ray analysis. The optical cut-off wavelength is observed to shift from 300 to 525 nm after the addition of SnS2 dopant on SeS crystals. Rod-like SeS and rod-like and platy SeSnS2 crystals are identified by optical microscopy. (C) 2004 Elsevier B.V. All rights reserved.