2024/02/01 by Lorenz Kranabetter, Kranabetter, Lorenz, Henrik H. Kristensen +5 · 1 citation
Engineering · Materials Science · Physics and Astronomy · #Atomic and Molecular Clusters (physics.atm-clus) #Atomic and Molecular Physics #FOS: Physical sciences #Laser-induced spectroscopy and plasma #Nuclear Materials and Properties
paper · pdf · doi:10.48550/arxiv.2402.00587
openalex publication_date 2024/02/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Alkali trimers, Ak3, located on the surface of He nanodroplets are triply ionized following multiphoton absorption from an intense femtosecond laser pulse leading to fragmentation into three correlated Ak+ ions. Combining the information from three-fold covariance analysis of the emission direction of the fragment ions and from their kinetic energy distributions P(Ekin), we find that Na3, K3, and Rb3 have an equilateral triangular structure, corresponding to that of the lowest-lying quartet state 4A2', and determine the equilibrium bond distance Req(Na3) = 4.65 ± 0.15 Å, Req(K3) = 5.03 ± 0.18 Å, and Req(Rb3) = 5.45 ± 0.22 Å. For K3 and Rb3 these values agree well with existing theoretical calculations, while for Na3 the value is 0.2-0.3 Å larger than the existing theoretical results. The discrepancy is ascribed to a minor internuclear motion of Na3 during the ionization process. Also, we determine the distribution of internuclear distances P(R) under the assumption of fixed bond angles. The results are compared to the square of the internuclear wave function |Ψ(R)|2.