The aim of this project is to investigate the chemistry of the material arsenic trisulfide (As2S3) in order to develop and adapt it for use as a photoresist with the 3-D direct laser writing (3-D DLW) method.  This material has both the advantage of high mechanical stability and high index of refraction (n = 2.45).  These properties allow complex 3-D photonic band gap (3-D PBG) structures, with a full 3-D PBG, to be easily fabricated.  This enables significant time and cost savings in the design and testing of 3-D PBG nanostructures as potential components in all-optical photonic circuits.