Marggi Poullaín, SoniaKobayashi, YukiChang, KristinaLeone, Stephen2024-01-152024-01-152021Poullain, Sonia M., et al. «Visualizing Coherent Vibrational Motion in the Molecular Iodine B 3 Π 0 + u State Using Ultrafast XUV Transient-Absorption Spectroscopy». Physical Review A, vol. 104, n.o 2, agosto de 2021, p. 022817. https://doi.org/10.1103/PhysRevA.104.022817.2469-992610.1103/PhysRevA.104.022817https://hdl.handle.net/20.500.14352/92998Attosecond probing of core-level electronic transitions in molecules provides a sensitive tool for real-time observation of chemical dynamics. Here, we employ ultrafast extreme-ultraviolet (XUV) transient-absorption spectroscopy to investigate the excited state electronic and nuclear dynamics in a prototype molecule, I2. A few-femtosecond visible pump pulse is employed to excite the I2 molecule and an attosecond XUV pulse is used to probe the dynamics through iodine-4d core-to-valence transitions. A highly extended vibrational wave packet (ν′=10–50,ν′max=25) is prepared by one-photon absorption in the valence excited B3Π0+u state of I2 and its motion is directly mapped due to the strong shift of the XUV core-level transition with internuclear separation. Through the imaging of this vibrational motion, we directly reconstruct the transition energy between the valence and the core-excited states as a function of internuclear distance. Besides single-photon dynamics, distinct direct dissociation pathways arising from two-photon pump absorption are also revealed.engAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/journal articlehttps://doi.org/10.1103/PhysRevA.104.022817open access544Absorption spectroscopyCore levelsDynamicsIodineMoleculesOptical pumpingParticle beamsPhotonsTwo photon processesUltrafast lasersQuímica física (Física)2206 Física Molecular2206.07-1 Espectroscopia láser