Pulse radiolysis is a method of studying reaction kinetics by following the time-resolved absorption or emission spectroscopy of transient species.While there is a long history of pulse radiolysis using UV-Vis-NIR detection, condensed phase absorption bands in these spectral regions are often broad and featureless. This paper by researchers at Brookhaven National Laboratory demonstrates the application of time-resolved vibrational spectroscopy methods to pulse radiolysis using a suite of narrow linewidth, mode-hop-free quantum cascade lasers. The Daylight Solutions' lasers offer high-power, CW, narrow linewidth output for studying a range of transient species with absorptions from 2330 to 1051 cm-1.