Photolysis (254 nm) of CF3N3 in pentane at 6−10 K produced a persistent electron paramagnetic resonance spectrum typical of a triplet nitrene centered at 8620 G. The spectrum (|D/hc| = 1.736 cm-1) is attributed to triplet CF3−N, and is very similar to that of triplet NH (|D/hc| = 1.863 cm-1) and CH3-N (|D/hc| = 1.720 cm-1) which were reported previously. CF3N3 was also deposited in an argon matrix at 14 K. The azide (λmax = 257 nm) was decomposed by exposure to 254 nm light with the concurrent formation of sharp, structured absorption bands at 342, 347.5, and 354 nm. The UV bands are assigned to the triplet nitrene CF3N on the basis of its similarity to the spectrum of CH3N and time-dependent density functional theory (B3LYP) calculations.