Fluorenylidene can be produced by photolysis of 9-diazofluorene (DAF). 
Ultra-fast (300 fs) time resolved laser-flash photolysis of DAF implicates a four-step process in the formation of fluorenylidene by irradiation of 9-diazofluorene. 
# Irradiation of DAF initially yields an excited singlet state diazofluorene 	molecule ( DAF*)
# DAF* decays to form the open shell carbene,FL*, as the minor product, 	and the less energetic closed shell carbene, FL, as the major product. 
# Any excited singlet FL* in solution relaxes to the lower energy singlet 	state FL (20.9 ps) 
# FL equilibrates with the ground state triplet FL by intersystem crossing.