The rotationally resolved UV spectra of the electronic origins of five isotopomers of the phenol dimer have been measured. The complex spectra are analyzed using a fitting strategy based on a genetic algorithm. The intermolecular geometry parameters have been determined from the inertial parameters for both electronic states and compared to the results of ab initio calculations.
View Article and Find Full Text PDFThe structure of benzimidazole has been determined in the electronic ground and excited states using rotationally resolved electronic spectroscopy. The rovibronic spectra of four isotopomers and subsequently the structure of benzimidazole have been automatically assigned and fitted using a genetic algorithm based fitting strategy. The lifetimes of the deuterated isotopomers have been shown to depend on the position of deuteration.
View Article and Find Full Text PDFThe hydrogen bond structure of the p-cyanophenol-water cluster has been determined in the ground and first excited electronic state by rotationally resolved UV spectroscopy. The water molecule is trans-linearly bound to the hydroxy group of the p-cyanophenol moiety, with hydrogen bond distances considerably shorter in both electronic states than in the similar phenol-water cluster. The structure of the cluster has been elucidated by ab initio calculations at various levels of theory and compared to the experimental findings.
View Article and Find Full Text PDFThe rotationally resolved S1<--S0 electronic origins of several deuterated resorcinol rotamers cooled in a molecular beam have been recorded. An automated assignment of the observed spectra has been performed using a genetic algorithm approach with an asymmetric rotor Hamiltonian. The structures of resorcinol A and resorcinol B were derived from the rotational constants of twenty deuterated species for both electronic states.
View Article and Find Full Text PDFThe structure of 4-methylphenol (p-cresol) and its binary water cluster have been elucidated by rotationally resolved laser-induced fluorescence spectroscopy. The electronic origins of the monomer and the cluster are split into four sub-bands by the internal rotation of the methyl group and of the hydroxy group in case of the monomer, and the water moiety in case of the cluster. From the rotational constants of the monomer the structure in the S1 state could be determined to be distorted quinoidally.
View Article and Find Full Text PDFThe conformational space of tryptamine has been thoroughly investigated using rotationally resolved laser-induced fluorescence spectroscopy. Six conformers could be identified on the basis of the inertial parameters of several deuterated isotopomers. Upon attaching a single water molecule, the conformational space collapses into a single conformer.
View Article and Find Full Text PDFThe laser induced fluorescence spectra of several torsional transitions of the S1 <-- S0 electronic transition were recorded for the hydroxy deuterated o- and m-cresols. Both cis and trans rotamers were observed in a high resolution molecular beam experiment. The spectra were analyzed using a genetic algorithm assisted automatic assignment.
View Article and Find Full Text PDFThe rotationally resolved LIF spectra of four different isotopomers of the phenol--nitrogen cluster have been measured to elucidate the structural parameters of the cluster in ground and electronically excited (S1) state. The fit of the rotational constants has been performed by a genetic algorithm and by an assigned fit to the line frequencies. The results of both methods are compared.
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