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We present a comparison of different molecular glasses based on the spiro-concept with respect to their photoemission properties. The absorption and emission spectra as well as the photoluminescence quantum yields in solution are characterized. For thin amorphous films, prepared by vacuum vapor deposition, we examined amplified spontaneous emission (ASE) by optical pumping with picosecond pulses at 337 nm. Efficient ASE emission with thresholds of down to 1 μJ/cm2 was observed. [Copyright &y& Elsevier]

We present measurements of amplified spontaneous emission (ASE) in films of spiro-sexiphenyl and higher branched spiro starburst compounds of the 1st and 2nd generation. Gain narrowing is observed at threshold intensities of approximately 3.2 μJ/cm2 when pumped with 500 ps pulses at 337 nm. A comparison of ASE peak wavelengths, linewidths and degradation kinetics in air is presented for the different spiro compounds. The ASE lines are the 1-0 fluorescence transitions of the three compounds at 419, 428 and 443 nm, respectively, with linewidths of approximately 3 nm. The dependence of ASE threshold on film thickness is explained in terms of waveguide optics. The lowest threshold is achieved for monomode films (100–150 nm). Photo-degradation effects occur in air atmospheres but can be suppressed in oxygen-free environments. [Copyright &y& Elsevier]