Time-Resolved Step-Scan Fourier Transform Infrared Spectroscopy

The time-resolved step-scan FTIR technique is used for investigations of transition metal complexes with 2 to 4 metal centers in the interval from nanoseconds to milliseconds. The vibrational frequencies obtained from this technique by comparison with theoretical predictions permit an assignment on the electronically excited and their corresponding structures as well the lifetimes of the electronically excited states. The step-scan FTIR technique is suitable for investigations in solution and in the solid state, which enables us to reveal solvent effects. A special focus in this project lies on cooperative effects between metal centers. These effects can lead to energetic shifts of electronic states or to changes of the electronically excited state lifetimes resulting from the exchange of metal atoms or by changing the number of metal centers.

Figure 1: Scheme for clarification of data aquisition with Step-Scan FTIR experiments.

Figure 2: Step-Scan FTIR spectrum (left) of the trinuclear palladium complex (right) from http://dx.doi.org/10.1039/C5CP00959F