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Updated: Jun 25, 2026

Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
Combined experimental and theoretical study of the benzocaine/Ar van der Waals system in supersonic expansions
Iker León1, Edurne Aguado, Alberto Lesarri
1Departamento de Quimica-Fisica, Facultad de Ciencia y Tecnologia, Universidad del Pais Vasco. Apdo. 644, 48080 Bilbao, Spain.
Abstract:
The electronic spectra of Benzocaine x Ar(n), n = 0-4 were obtained using two-color resonance enhanced multiphoton ionization; the 1:1 and 1:2 clusters were investigated by ultraviolet/ultraviolet hole burning, stimulated emission pumping, and other laser spectroscopies. A single isomer was found for the 1:1 cluster, while two isomers of the 1:2 cluster were found: one with the two Ar atoms on the same side of the chromophore, and the other with the two Ar atoms sitting on opposite sides of the chromophore. The observed shifts point to the existence of a single isomer for the 1:3 and 1:4 species. Dissociation energies for the neutral ground and first excited electronic state and the ion ground electronic state of the complexes have been determined by the fragmentation threshold method and by ab initio calculations conducted at the MP2 level with 6-31++g(2d, p), 6-311++g(2d, p) and AUG-cc-pVTZ basis sets. The results are compared with those obtained for other similar systems.
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