With support from the Chemistry Research Instrumentation and Facilities Multiuser Instrumentation (CRIF-MU) Program, the Department of Chemistry at Colorado State University will purchase a surface sum frequency generation (SFG) spectrometer. The SFG spectrometer will be utilized in the following research projects: 1) surfactant order/disorder at reverse micelles interfaces; 2) nanoparticle growth and surface chemistry; 3) plasma deposition/plasma surface modification; 4) chiral surfaces; 5) polyaromatic hydrocarbon surfaces; 6) photoinduced charge separation; and 7) substrates for selective detection of molecular binding events.
A surface SFG spectrometer can be used to explore chemistry occurring at solid and liquid interfaces in situ. The SFG is based on an ultrashort pulsed laser system that generates broadband infrared (IR) radiation allowing collection of signal from a significant spectral range for each laser pulse. The SFG signal arises from combination of the broad IR radiation with a narrow visible pulse which is then detected by a CCD detector. Thus, data can be acquired for the vibrational spectrum for each laser pulse. The system can also be scanned over a range of frequencies to acquire data over a spectral range broader than the individual laser pulse. So far, SFG has been utilized extensively as a probe of molecular vibrations at surfaces and interfaces (solid/gas, liquid/air, liquid/solid, liquid/liquid, and solid/solid).
