Fig. 4
From: Muon spectroscopy of a 12-phosphatetraphene with extremely efficient radical trapping properties

(a) µLCR spectra of a 0.060 M solution of 1 in THF. The error bars are smaller than the data points. (b) Regioselective addition of muonium to the sp2-type phosphorus in 1, generating paramagnetic 1Mu.