Mass spectrometric studies of the phosphorus sulphides

Abstract

The mass spectra of P₄Se₃, P₄S₃, P₄S₅, P₄S₇, and P₄S₁₀ are reported; all exhibit molecular ions, but are otherwise dominated by even-electron ions, especially PS⁺, P₃S⁺, and P₃S₄⁺. P₃S⁺ and P₃S₄⁺ may possess the P₄ and P₄S₃ structures respectively, but with S⁺ replacing P. The only abundant odd-electron ions other than molecular ions are P₂S₅⁺ and P₂S₃⁺, observed in the spectrum of P₄S₁₀; this indicates dissociation of P₄S₁₀ into P₂S₅ molecules in the vapour phase, consistent with the reported vapour density. The spectra of frozen melts of composition P₄S_7–10 provide evidence for the presence of P₄S₉ molecules but not P₄S₈ molecules.