Structural deductions using (i) symmetric–antisymmetric stretching-frequency correlations for sulphur–oxygen and sulphur–nitrogen groups and (ii) stretching-wavelength–bond-distance correlations for sulphur–oxygen and sulphur–nitrogen bonds

Abstract

We have re-examined vibrational data for the well known linear relationship between symmetric and antisymmetric SO₂ stretching frequencies in a wide range of sulphur–oxygen compounds, and propose a more precise correlation for sulphuryl compounds, RR′SO₂, where R and R′ can be alkyl, alkoxy, aryl, aryloxy, amido, amino, imido, imino, halogeno, pseudohalogeno, siloxy and vinyl groups. A similar improved relationship between ν_s and ν_as is reported for sulphur diamides and di-imides. We also describe linear correlations between vibrational stretching wavelength and bond distance for both sulphur–oxygen and sulphur–nitrogen compounds. The correlations can be used to calculate approximate bond distances in species for which only vibrational data are available. Using a new linear regression procedure, estimated errors in the deduced distances can be calculated.