Fast observation of primary triplets in naphthalene vapor with tandem laser pulse absorption

A sharply tuned pulsed laser absorption experiment is described involving two dye lasers synchronized in tandem (TLPA) which enables one to produce molecules in defined excited states and then follow the immediate production of subsequent molecular species. Measurements of transient TT absorption were carried out in naphthalene at pressures down to 20 mtorr with a precision of 0.2%. The results demonstrate the feasibility of TLPA and here specifically that triplets are formed in naphthalene as a prompt process, and that collisions do not aid the formation of these primary product species.