Muon spin rotation (µSR) study of a sterically encumbered thioaldehyde

Abstract Here we report a preliminary muon spin rotation (µSR) analysis of a sterically encumbered 2,4,6-tri-t-butylthiobenzaldehyde. A powder sample of the thiobenzaldehyde was placed in a beam of positive muons, and the transverse-field muon spin rotation (TF-µSR) spectroscopy was performed. The observed muon-electron hyperfine coupling constant (Aµ) was considerably smaller than that of cyclohexadienyl radicals, indicating that the aromatic ring in the thiobenzaldehyde did not capture muonium (Mu = µ+e–). DFT calculations concluded that Mu added to the C = S sulfur atom, which was comparable to the previous report on thiobenzophenone. Graphical Abstract

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