Stopped-flow rapid-scan Fourier transform infrared spectroscopy

A stopped-how rapid-mixing device intel faced with a rapid-scan FT-IR spect rometer and a diode-array UV-visible spectrophotometer permits the observat ion of reaction transient intermediates over a broad range of wavelengths a t minimal cost. The system has been evaluated for both spectral regions wit h the use of two different chemical reaction systems. The presence of a tra nsient intermediate is clearly indicated in one case. Unexpected reactivity was ol,served in the other case. This approach will allow the study of che mical reactions even when no spectral changes occur in the UV-visible regio n.