Instrumentation for steady-state and dynamic fluorescence and absorbance studies in supercritical media

We describe and characterize a new instrument for the measurement of: (1) steady-state excitation, emission, and absorbance spectra; (2) fluorescence lifetimes; and (3) phase-resolved fluorescence spectra in supercritical fluid media. Time resolution is on the order 10-20 ps, spectral resolution is 1 nm from 225-700 nm, and pressure and temperature can be controlled accurately and safely from 1 to 300 ± 0.7 atm and 273.2 to 373.2 ± 0.1 K, respectively. The instrument shows great promise for the elucidation of complex solvation processes occurring in supercritical fluid media.