NEW TYPE OF TRIPLET SPECIES IN TCNQ ION-RADICAL SALTS

New triplet states in the ion-radical salt ø3AsCH 3+(TCNQ)2- over and above the regular triplet exciton state are reported. These states are characterized by the properties of their ΔM=l spectra. At least one of the triplet states is an excited state with a singlet-triplet splitting of 2.5 cm-1. The maximum values of the zero-field splittings and the limited angular dependence of the spectra appear to indicate that the triplets arise from two unpaired electrons delocalized over sites located on different adjacent TCNQ chains. The lack of hyperfine structure is interpreted to indicate that there may be some motion associated with one or all of the triplet entities, but that this motion, if it exists, is slower than that of the regular exciton.