DIRECT LOG RATIO RECORDING RAPID SCANNING SPECTROPHOTOMETER

A double beamed, direct log ratio recording, rapid scanning spectrophotometer (RSS) which scans the wavelength range of 3700 to 7000 Å or any width of that range at repetitive velocities up to 4000 Hz has been built in our laboratory. The signal-to-noise ratio, wavelength resolution, and absorbance sensitivity depend on the scan velocity, but absorbance changes of less than 0.02 unit and a resolution of 20 Å at a scan rate of 1000 Hz have been obtained. Instrumental design and capabilities are discussed. The use of the RSS for following intermediates and products during electrolyses at optically transparent electrodes is presented. © 1969, American Chemical Society. All rights reserved.