The general theme of our research centers on the use of various techniques of time-resolved laser spectroscopy to investigate condensed phase chemical reaction dynamics in metalloproteins and small molecule systems having a biological or environmental significance. For example, we are currently interested in gaining a comprehensive understanding of the chemistry exhibited by dioxygen activation- and transport-proteins. Our interest in this area is motivated by our desire to develop efficient dioxygen carriers for blood substitutes. We are seeking to determine how the active-site electronic and structural features of non-heme dioxygen transport and activation proteins control their reactions with dioxgyen. The methods of ultrafast laser spectroscopy used in our laboratory include time-resolved absorption and polarization spectroscopy, as well as photoacoustic calorimetry. The instrumentation required for these experiments involves a self-mode-locked titanium:sapphire laser oscillator, regenerative amplifier and optical parametric oscillator. The laser spectrometer allows us to produce sub-100-fs pulses over much of the 300-nm-10-μm spectral regions.