A universal chemical potential for sulfur vapours

Thumbnail Image
c5sc03088a.pdf(1.28 MB)
Published version
Jackson, Adam J.
Tiana, Davide
Walsh, Aron
Journal Title
Journal ISSN
Volume Title
Royal Society of Chemistry (RSC)
Published Version
Research Projects
Organizational Units
Journal Issue
The unusual chemistry of sulfur is illustrated by the tendency for catenation. Sulfur forms a range of open and closed S-n species in the gas phase, which has led to speculation on the composition of sulfur vapours as a function of temperature and pressure for over a century. Unlike elemental gases such as O-2 and N-2, there is no widely accepted thermodynamic potential for sulfur. Here we combine a first-principles global structure search for the low energy clusters from S-2 to S-8 with a thermodynamic model for the mixed-allotrope system, including the Gibbs free energy for all gas-phase sulfur on an atomic basis. A strongly pressure-dependent transition from a mixture dominant in S-2 to S8 is identified. A universal chemical potential function, mu(S)(T,P), is proposed with wide utility in modelling sulfurisation processes including the formation and annealing of metal chalcogenide semiconductors.
Electronic-structure , Elemental sulfur , Crystal-growth , Scale factorS , Scale factors , Free-energy , Prediction , CU2ZNSNS4 , Model , S-4 , Tetrasulfur
Jackson, A. J., Tiana, D. and Walsh, A. (2016) 'A universal chemical potential for sulfur vapours', Chemical Science, 7(2), pp. 1082-1092. doi: 10.1039/c5sc03088a