A Rapid-Scan Infrared Spectrometer; Flash Photolytic Detection of Chloroformic Acid and of CF_2

Abstract

A rapid-scan infrared spectrometer has been constructed and successfully applied to the study of short-lived intermediates produced by flash photolysis. A zinc-doped germanium semiconductor detector and a high-speed rotating Littrow mirror permit scan rates of 1000 cm−1/100 μsee through the region 5000–650 cm−1. Two transient species, chloroformic acid and CF2, have been identified, and lough estimates of their lifetimes have been obtained, 50–70 μsec and about 2.5 msec, respectively. This is the first spectroscopic detection of chloroformic acid.