On the apparent absence of triplet-triplet absorption in pure organic molecular crystals

Abstract

The triplet-triplet absorption spectra of naphthalene-h 8 in a 3-methylpentane glass at 77 K and naphthalene-h 8 in a naphthalene-d 8 crystal at 4·2 K are reported. A broad continuum absorption unique to the mixed crystal spectrum is believed to be due to a guest-induced transition into the host conduction band. Absence of the absorption in pure crystals of naphthalene at temperatures ranging from 1·8 K to 300 K is also discussed.