Solvation Induced Vibrational Peak Shift of a Re Bipyridyl Complex in Solution and at the Nanoporous ZrO2/Liquid Interface

In this paper, we compare the solvation induced vibrational peak shift of Re(CO) 3 (Cl)(2,2‘-bipyridine-4,4‘-carboxylate) in solution and at nanocrystal/liquid interfaces. Upon optical excitation to its MLCT excited state, an instantaneous blue shift in CO stretching frequency is observed, which is followed by slower shifts on the few hundred picosecond time scale. The amplitude and dynamics of the latter shift are solvent dependent. In bulk alcohols, the peak shift amplitude decreases and dynamics slow in longer chain alcohols. At the interfaces, the peak shift amplitude is smaller and dynamics are slower than those in the corresponding bulk solution. We attribute these vibrational peak shift dynamics to solvation process and utilize them to compare solvation dynamics in bulk solution and at nanoparticled/liquid interfaces.