THE SPECTRUM OF $S_{3}$ AND $S_{4}$

Abstract

We have studied a long-known but unanalyzed system of bands in the region 360-450 nm caused by an elusive species in unsaturated sulfur at $300^{\circ} C$ to $650^{\circ} C$. All vibrational band heads fit a progression of $v^{\prime\prime}\sim 400 cm^{-1}$ and $v^{\prime}\sim$ 640 $cm^{-1}$. The origin, located with the help of $^{34}$S, is at 23 601 $cm^{-1}$. The vapor species is here identified as $S_{3}$ thiozone, because the spectrum can be obtained in a krypton matrix at $20^{\circ} K$ and in an organic glass at $77^{\circ} K$ when $S_{3}Cl_{2}$ is photolyzed at low temperature. A continuum in the absorption spectrum of sulfur vapor in the 530 nm region is shown to be due to $S_{4}$, which can be synthesized by the photolysis of $S_{4}$ $Cl_{2}$ in a low temperature glass.