2,3‐Dichloroanthracene crystal, a new rigid matrix for single molecule optical investigations

Absorption and emission spectra of single crystals of 2,3‐dichloroathracene (23DCA) and 23DCA dispersed in n‐nonane matrix were studied at 5 K. Singlet and triplet excitonic bands in the crystal were estimated to be at about 415 nm and at wavelengths shorter than 700 nm, respectively. Thus, from the spectroscopic point of view these crystals provide a new, transparent and rigid matrix for low temperature optical studies of single molecules of dibenzoterrylene, which have their purely electronic S0→S1 transition at around 785 nm. Quantum‐chemistry calculation were used to analyze the spectra.