| Rydberg Fingerprint spectroscopy (RFS) has been shown to be very useful in molecular structure characterization, because the Rydberg electrons are sensitive to the potential of the molecular ion core. To illustrate this principle, two series of isomers, C10H8 and C6H 8, have been examined. The Rydberg fingerprint spectra clearly show the differences between isomeric structures, indicating the sensitivity of Rydberg states to the shapes of molecules. RFS has also been used to study the local photoionization and charge transfer dynamics of 2-phenylethyl-N,N-dimethylamine (PENNA). PENNA can be ionized in multiphoton processes using different laser wavelengths. As the Rydberg fingerprint spectra illustrate, it is possible to locally ionize specific chromophores in a single molecule by changing excitation laser wavelength. Finally, RFS has been used to study the ultrafast dynamics of the ring opening of 1,3-cyclohexadiene (CHD). The Rydberg fingerprint spectra confirm the existence of one dark state 2A1 and a superexcited state during ionization process and present two distinct Rydberg series with different quantum defects. These results show that RFS provides a versatile and useful new way of determining molecular properties. |
