The Molecular Structures of the Polysulfuryl Fluorides by Vapor Phase Electron Diffraction: S2O5F2 and S3O8F2

Abstract

The molecular structures of the polysulfuryl fluorides, S2O5F2 and S3O8F2, were determined by vapor phase electron diffraction. In each case it was assumed that a single rotomer was more stable than all others, by at least 2.5 kcal mol−1. The possibility that the sample consisted of a mixture of conformations of comparable stabilities was not explored.The thermally averaged rg parameters for S2O5F2 are as follows: S=O = 1.398 ±.002 Å; S—F = 1.525 ± 0.005 Å; S—O = 1.611 ± 0.005 Å; ∠SOS = 123.6 ± 0.5°; ∠OS=O = 106.1 ± 0.9°; ∠FS=O = 106.6 ± 0.6°; ∠O=S=O = 126.8 ± 1.2°; ∠OSF = 102.4 ± 1.8°; τFS/OS′ = 53.8 ± 2.7°; τF′S′/OS = 73.7 ± 2.4°. The rg parameters for S3O8F2 are: S=O = 1.402 ± 0.003 Å; S—F = 1.525 ± 0.012 Å; S—O = 1.613 ± 0.006 Å; ∠OSO = 97.8 ± 1.0°; ∠SOS = 123.6 ± 1.2°; ∠OS=O = 106.5 ± 0.8°; ∠FS=O = 105.5 ± 1.2°; ∠O=S=O (bridge) = 128.8 ± 1.4°; ∠O=S=O = 128.5 ± 1.4°; ∠OSF = 101.3 ± 1.5°; τSO/SO = 295.3 ± 0.9°; τFS/OS = 319.4 ± 2.2°. The standard errors listed are three times the calculated values and are believed to encompass the non-random errors in the analysis.