Preparation of high-purity vitreous B2S3

Preparation schemes for high-purity vitreous B2S3 (v-B2S3) with a S:B ratio of 1.478 ± 0.032 are described. Preparation schemes reported in the literature are shown by very sensitive FT-IR measurements to yield v-B2S3 with significant oxygen contamination. Through extreme care taken in carbonizing silica reaction tubes and through the use of very high purity starting materials, oxygen contamination of less than 1% has been achieved. The IR spectrum for very pure v- B2S3 contains only two absorption bands