| 1. |
- Iablonskyi, D., et al.
(författare)
-
Slow Interatomic Coulombic Decay of Multiply Excited Neon Clusters
- 2016
-
Ingår i: Physical Review Letters. - 0031-9007. ; 117:27
-
Tidskriftsartikel (refereegranskat)abstract
- Ne clusters (∼5000 atoms) were resonantly excited (2p→3s) by intense free electron laser (FEL) radiation at FERMI. Such multiply excited clusters can decay nonradiatively via energy exchange between at least two neighboring excited atoms. Benefiting from the precise tunability and narrow bandwidth of seeded FEL radiation, specific sites of the Ne clusters were probed. We found that the relaxation of cluster surface atoms proceeds via a sequence of interatomic or intermolecular Coulombic decay (ICD) processes while ICD of bulk atoms is additionally affected by the surrounding excited medium via inelastic electron scattering. For both cases, cluster excitations relax to atomic states prior to ICD, showing that this kind of ICD is rather slow (picosecond range). Controlling the average number of excitations per cluster via the FEL intensity allows a coarse tuning of the ICD rate.
|
|
| 2. |
- Jahnke, T., et al.
(författare)
-
Inner-Shell-Ionization-Induced Femtosecond Structural Dynamics of Water Molecules Imaged at an X-Ray Free-Electron Laser
- 2021
-
Ingår i: Physical Review X. - : American Physical Society. - 2160-3308. ; 11:4
-
Tidskriftsartikel (refereegranskat)abstract
- The ultrafast structural dynamics of water following inner-shell ionization is a crucial issue in high-energy radiation chemistry. We have exposed isolated water molecules to a short x-ray pulse from a free-electron laser and detected momenta of all produced ions in coincidence. By combining experimental results and theoretical modeling, we can image dissociation dynamics of individual molecules in unprecedented detail. We reveal significant molecular structural dynamics in H2O2+, such as asymmetric deformation and bond-angle opening, leading to two-body or three-body fragmentation on a timescale of a few femtoseconds. We thus reconstruct several snapshots of structural dynamics at different time intervals, which highlight dynamical patterns that are relevant as initiating steps of subsequent radiation-damage processes.
|
|
| 3. |
|
|
| 4. |
- Musin, R. N., et al.
(författare)
-
Magnetic properties of Cu(II) bischelate complexes with 3-imidazoline nitroxides. 1. An ab initio analysis of spin density delocalization channels
- 1997
-
Ingår i: Journal of Structural Chemistry. ; 38:5, s. 703-710
-
Tidskriftsartikel (refereegranskat)abstract
- Spin density redistribution between the paramagnetic centers CU2+, N-O, and N'-O' of bischelate complexes CuL2 of the copper ion with enaminoketone 3-imidazoline nitroxides (L) are investigated using an ab initio RHF (restricted Hartree-Fock) approach. The most important channels of unpaired electron delocalization over the systems of pi- and sigma-bonds in such complexes are revealed. The conformation dependence of spin density localized on paramagnetic centers and delocalized due to a distortion of the structure of the environment of the CU2+ ion from square planar to tetrahedral is analyzed and explained.
|
|
| 5. |
- Takanashi, T, et al.
(författare)
-
Time-Resolved Measurement of Interatomic Coulombic Decay Induced by Two-Photon Double Excitation of Ne2
- 2017
-
Ingår i: Physical Review Letters. - 0031-9007. ; 118:3
-
Tidskriftsartikel (refereegranskat)abstract
- The hitherto unexplored two-photon doubly excited states [Ne∗(2p-13s)]2 were experimentally identified using the seeded, fully coherent, intense extreme ultraviolet free-electron laser FERMI. These states undergo ultrafast interatomic Coulombic decay (ICD), which predominantly produces singly ionized dimers. In order to obtain the rate of ICD, the resulting yield of Ne2+ ions was recorded as a function of delay between the extreme ultraviolet pump and UV probe laser pulses. The extracted lifetimes of the long-lived doubly excited states, 390(-130/+450) fs, and of the short-lived ones, less than 150 fs, are in good agreement with ab initio quantum mechanical calculations.
|
|
