Further Study of the two Forms of Liquid Sulphur as Dynamic Isomers

Extract

When sulphur to which after recrystallisation no air has had access is melted, or when ammonia is led for a few minutes through ordinary sulphur after it has been melted, the two forms of liquid sulphur (yellow, mobile S_λ, and brown, viscous S_μ) adjust themselves very rapidly to those proportions which are in equilibrium at that temperature to which the liquid may have been raised. The adjustment occupies but a few moments. When specimens thus prepared are then chilled by plunging into water, the reversion of the S_μ to S_λ is equally rapid, and therefore the product is wholly brittle, crystalline, monoclinic sulphur. This behaviour is observed whether the liquid has been heated at, say, 155°, where the amount of S_μ, at equilibrium is 7·2 per cent., or at 448°, where the amount is at least 34 per cent.