Electrochemical and electronic structure investigations of the [S3N3]* radical and kinetic modeling of the [S4N4]n/[S3N3]n (n = 0, -1) interconversion.

摘要: Voltammetric studies of S4N4 employing both cyclic (CV) and rotating disk (RDE) methods in CH2Cl2 at a glassy carbon electrode reveal one-electron reduction −1.00 V (versus ferrocene/ferrocenium), which produces second redox couple −0.33 V, confirmed to be the electrochemically generated [S3N3]− by CV on its salts. Diffusion coefficients (CH2Cl2/0.4 M [nBu4N][PF6]) estimated RDE methods: S4N4, 1.17 × 10−5 cm2 s−1; [S3N3]−, 4.00 10−6 s−1. Digital simulations CVs detected slow rates electron transfer for couples allowed determination rate constants homogeneous chemical reaction steps subsequent transfer. The common parameters (kf1 = 2.0 ± 0.5 s−1, ks1 0.034 0.004 cm s−1 [S4N4]−/0; kf2 0.4 0.2 ks2 0.022 0.005 [S3N3]−/0 T 21 2 °C) fit well “square-scheme” mechanism over entire range data with first order decay products. An alternate model could also wherein [NS]• liber...