Abstract Three conformers of cyclohexylallene, designated I, II and III, were observed in the IR and Raman spectra. Metastable crystals formed by annealing an amorphous solid from 80 K to 140 K, and crystals formed under a pressure of 30 kbar at ambient temperature, contained conformer II. The stable crystals obtained after heating the metastable crystals to 195 K contained conformer I. The conformer III was observed as a minor component in a ...