2026-03-09T09:22:27Zhttps://uvadoc.uva.es/oai/request

oai:uvadoc.uva.es:10324/729282025-01-12T18:01:40Zcom_10324_1186com_10324_931com_10324_894col_10324_1404

00925njm 22002777a 4500 dc Castillo Delgado, Roger author Blanco Rodríguez, Susana author López Alonso, Juan Carlos author 2024 The rotational spectrum of laser ablated trans-3-methoxycinnamic acid has been observed in the 2–8 GHz range using chirped-pulse Fourier transform microwave spectroscopy coupled to a supersonic jet and adapted to support a laser ablation vaporization system (LA-CP-FTMW). Eight stable conformers were theoretically predicted to exist at B3LYP-D3BJ/6–311++(2d,p) level, all of which were experimentally detected. The experimental rotational parameters data evidence the essentially planar structures for all the conformers. The relative population distribution of conformers in the supersonic jet was investigated from relative intensity measurements. Cooling in the jet brings rotational temperatures close to 1 K for all the conformers. The theoretical predictions for the rotational constants and electric dipole moments show good agreement with the experimental constants and selection rules observed. The population distribution of conformers in the supersonic jet was found to be close to the equilibrium distribution calculated at temperatures lower than the stagnation temperature. Finally, the correlation of the observed conformers structures with those found in condensed phases was investigated. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, abril 2024, vol. 311, 123997 1386-1425 https://uvadoc.uva.es/handle/10324/72928 10.1016/j.saa.2024.123997 123997 Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 311 Conformational isomerism in trans-3-methoxycinnamic acid: from solid to gas phase