Boron sulfide
Boron sulfide is the chemical compound with the formula BS. This polymeric material that has been of interest as a component of "high-tech" glasses and as a reagent for preparing organosulfur compounds. Like the sulfides of silicon and phosphorus, BS reacts with water, including atmospheric moisture to release HS. Thus, samples must be handled under anhydrous conditions. Like the boron oxides, BS readily forms glasses when blended with other sulfides such as PS. Such glasses absorb lower frequencies of Infra-red energy relative to conventional borosilicate glasses. BS converts ketones into the corresponding thiones. For example, the  conversion of benzophenone to its thione proceeds as follows: In practice, BS would be used in excess. Synthesis. Among other methods Diboron Trisulfide can be obtained by the reaction of iron or manganese boride with hydrogen sulfide at temperatures of 300 °C. The first synthesis was done by Jöns Jakob Berzelius in 1824 by direct reaction of amorphous boron with sulfur vapor. Another synthesis was favoured by Friedrich Wöhler and Henri Etienne Sainte-Claire Deville first published in 1858, starting from boron and hydrogen sulfide. Structure. The boron atoms in BS are trigonal planar, and are arranged in BS  and BS rings with bridging S atoms forming a layer structure with an interlayer distance of 355 pm. This is different from boron trioxide which has a three dimensional structure. The molecular, monomeric, form of BS has a planar V shape with the central B-S-B angle of approximately 120°.