Dr. Christopher Brazier
- CHEM 111A, General Chemistry
- CHEM 371A/B, Physical Chemistry
- CHEM 373, Physical Chemistry Lab
- CHEM 572, Advanced Physical Chemistry
My main research interest is the application of spectroscopic techniques to determine the properties of small gas phase molecules. My current research involves the characterization of small free radicals such as B2, AlC, AlB, and SiB by observing their electronic emission spectra in a corona excited supersonic expansion (CESE) source. This apparatus uses a high voltage power source to generate an electric discharge, or corona, in the throat of a supersonic expansion through a glass nozzle. A high speed vacuum pump is used to quickly sweep away the products. The discharge serves to break up the precursor molecule which is seeded in high pressure helium gas flowing through the nozzle. The atoms or fragments recombine producing the molecules of interest in excited electronic states. The light emitted by the excited molecules is dispersed by a 1.3m spectrometer and recorded on a CCD camera detector. The behavior of the source can be observed in real-time as the conditions are changed, this is important since the ideal nozzle conditions are hard to maintain.
The spectra of the electronically and vibrationally hot but rotationally cold molecules provide information on the energies and bonding in many different electronic states of these molecules. Much of the work involves searching through the spectra obtained for characteristic features of the species of interest. In many cases higher resolution spectra are subsequently recorded using the 1m Fourier transform spectrometer at Kitt Peak National Observatory in Arizona.