Dynamics of photoexcited Ba{sup +} cations in {sup 4}He nanodroplets

Journal Article · Mon Mar 07 04:00:00 EST 2016 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.4942850· OSTI ID:22660883

Leal, Antonio; Pi, Martí ^[1]; Zhang, Xiaohang; Drabbels, Marcel ^[2]; Barranco, Manuel ^[1]; Cargnoni, Fausto ^[3]; Hernando, Alberto ^[4]; Mateo, David ^[5]; Mella, Massimo ^[6]

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1. Departament ECM, Facultat de Física, and IN"2UB, Universitat de Barcelona, Diagonal 645, 08028 Barcelona (Spain)
2. Laboratoire de Chimie Physique Moléculaire, Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015 Lausanne (Switzerland)
3. Istituto di Scienze e Tecnologie Molecolari (ISTM), Consiglio Nazionale delle Ricerche, via Golgi 19, 20133 Milano (Italy)
4. Social Thermodynamics Applied Research (SThAR), EPFL Innovation Park, Bâtiment C, CH-1015 Lausanne (Switzerland)
5. Department of Chemistry and Biochemistry, California State University at Northridge, Northridge, California 91330 (United States)
6. Dipartimento di Scienza ed Alta Tecnologia, Università degli Studi dell’Insubria, via Valleggio 11, 22100 Como (Italy)

We present a joint experimental and theoretical study on the desolvation of Ba{sup +} cations in {sup 4}He nanodroplets excited via the 6p ← 6s transition. The experiments reveal an efficient desolvation process yielding mainly bare Ba{sup +} cations and Ba{sup +}He{sub n} exciplexes with n = 1 and 2. The speed distributions of the ions are well described by Maxwell-Boltzmann distributions with temperatures ranging from 60 to 178 K depending on the excitation frequency and Ba{sup +} He{sub n} exciplex size. These results have been analyzed by calculations based on a time-dependent density functional description for the helium droplet combined with classical dynamics for the Ba{sup +}. In agreement with experiment, the calculations reveal the dynamical formation of exciplexes following excitation of the Ba{sup +} cation. In contrast to experimental observation, the calculations do not reveal desolvation of excited Ba{sup +} cations or exciplexes, even when relaxation pathways to lower lying states are included.

• OSTI ID: 22660883
• Journal Information: Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Journal Issue: 9 Vol. 144; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
BARIUM IONS
BOLTZMANN STATISTICS
CATIONS
DENSITY FUNCTIONAL METHOD
EXCITATION
EXPERIMENTAL DATA
HELIUM 4
NANOSTRUCTURES
TIME DEPENDENCE