Photodissociation of mono- and di-anionic tin clusters

Negatively charged tin clusters offer a broad range of decay products, as observed after electron-cluster interactions [S. König, M. Wolfram, S. Bandelow, G. Marx, L. Schweikhard, Eur. Phys. J. D 72, 153 (2018)]. To get further insight into their decay pathways, size and charge-state selected clusters Snn- and Snn2- were photo-excited at the ClusterTrap setup by 532 nm Nd:YAG laser pulses. For small mono-anionic precursor clusters containing up to n ≃ 45 atoms, Snn-7- and Snn-10- are observed as preferred ionic fragments. For bigger clusters a transition to neutral monomer evaporation was found. In the case of di-anionic precursors, preferred decay products are Sn10- and Snn-10-, indicating fission similar to the case of the group 14 neighbor element lead [S. König, A. Jankowski, G. Marx, L. Schweikhard, M. Wolfram, Phys. Rev. Lett. 120, 163001 (2018)]. Furthermore, doubly charged fragment clusters such as Snn-72- are observed, originating from break-off of neutral heptamers Sn7, a behavior which has not been observed previously for di-anionic clusters. Graphical abstract

FMR in Ferromagnet with Electron Spin-Orbital Clusters

The spin-orbital subsystem model with electron clusters was used for studying the frequency spectra ferromagnetic resonance (FMR). A new type of ferromagnetic order and new region of FMR were found. The new region may be in the microwave region or in the infrared region (IR). The volume of spin-orbital electron cluster is equal to 1-50 cubic nanometer approximately.

PLASMON EXCITATIONS IN METAL CLUSTERS AND FULLERENES

This paper gives a survey of physical phenomena manifesting themselves in electron and photon collisions with atomic clusters. The emphasis is made on electron scattering, photoabsorption and photoionization of fullerenes and metal clusters, however some results are applicable to other types of clusters as well. It is demonstrated that the diffraction and interference phenomena play an important role in the processes of clusters interaction with photons and electrons. The essential role of the multipole surface and volume plasmon excitations is elucidated in the formation of electron energy loss spectra on clusters as well as in the total inelastic scattering cross sections and in multiphoton absorption regime. Attention is paid to the elucidation of the role of the polarization interaction in low energy electron-cluster collisions. This problem is considered for the electron attachment to metallic clusters and the plasmon enhanced photon emission. The mechanisms of electron excitation widths formation and the relaxation of electron excitations in metal clusters and fullerenes are discussed.