| 1. |
- Niskanen, Johannes, et al.
(författare)
-
Valence photoionization of the LiCl monomer and dimer
- 2010
-
Ingår i: Physical Review A. Atomic, Molecular, and Optical Physics. - 1050-2947 .- 1094-1622. ; 81:4, s. 043401-
-
Tidskriftsartikel (refereegranskat)abstract
- This paper reports a study of valence photoionization of the LiCl monomer and dimer. The behavior of the photoionization partial cross section for molecular valence orbitals was measured as a function of photon energy between 15 and 35 eV. A square-integrable-function method was used to model the ionization partial cross section in both the LiCl monomer and dimer.
|
|
| 2. |
- Fritzsche, S., et al.
(författare)
-
Photoelectron satellite structure from the 3d and 4d inner-shell ionization of rubidium and cesium: Role of atomic relaxation
- 2008
-
Ingår i: Physical Review A (Atomic, Molecular and Optical Physics). - 1050-2947. ; 78:3
-
Tidskriftsartikel (refereegranskat)abstract
- The photoelectron satellite structure of rubidium and cesium has been investigated following the photoionization of an nd (n= 3,4) inner-shell electron. The intensity ratios of the nd(-1) ms monopole and nd(-1) m'p conjugated satellite lines have been measured at MAX-lab by using high-resolution electron spectroscopy. For rubidium, moreover, the energy dependence of the 3d(j)6s/3d(j)5s and 3d(j)5p/3d(j)5s intensity ratios with j=3/2 and 5/2 is measured and compared with multiconfiguration Dirac-Fock calculations. A good or at least reasonable agreement is found for both the monopole and conjugated shake-up probabilities if the relaxation of the bound-state electron density is taken into account in the computation of the photoionization cross sections. It is shown that, for the inner-shell ionization of medium and heavy atoms, the orbital relaxation accounts for a significant part of the satellite structure in the photoelectron spectra.
|
|
| 3. |
- Jankala, K., et al.
(författare)
-
Analysis of 3d photoionization and subsequent Auger decay of atomic germanium
- 2011
-
Ingår i: Physical Review A (Atomic, Molecular and Optical Physics). - 1050-2947. ; 84:5
-
Tidskriftsartikel (refereegranskat)abstract
- Experimental and theoretical study of the 3d photoionization and subsequent Auger decay of initially neutral atomic germanium is presented. The features of the high-resolution photoelectron and Auger electron spectra are interpreted with the aid of multiconfiguration calculations. The binding energies and relative cross sections of the 3d ionized fine-structure states of Ge are given. The complete M4,5NN Auger electron spectrum to doubly ionized final states of the Ge ion is interpreted and discussed.
|
|
| 4. |
- Jankala, K., et al.
(författare)
-
Inner-shell 2p photoionization and Auger decay of atomic silicon
- 2008
-
Ingår i: Physical Review A (Atomic, Molecular and Optical Physics). - 1050-2947. ; 77:6
-
Tidskriftsartikel (refereegranskat)abstract
- A detailed experiment on 2p photoionization and subsequent Auger decay of atomic silicon is presented. Fine-structure-resolved photoelectron and Auger electron spectra are interpreted with the aid of large-scale multiconfiguration calculations. Energy separation and the relative cross sections of the 2p ionized fine-structure states of Si+ are given. The complete 2p Auger electron spectrum of Si is interpreted, and the intensity distribution to individual doubly ionized final states is studied.
|
|
| 5. |
- Karpenko, A., et al.
(författare)
-
Behavior of relative state selective photoionization cross sections of RbBr molecules in the valence region
- 2014
-
Ingår i: Physical Review A (Atomic, Molecular and Optical Physics). - 1050-2947. ; 90:6
-
Tidskriftsartikel (refereegranskat)abstract
- The photon energy dependence of relative photoionization cross sections in the valence ionization energy region of 5 to 45 eV for 4p and 4s orbitals of Rb and Br ions in RbBr vapors has been investigated. The behavior of state selective cross sections of molecular valence orbitals has been analyzed by comparing the observed 4p to 4s photoelectron intensity branching ratios with atomic state selective photoionization cross sections of Kr, taking into account the mixing between Br 4s(-1) and Rb 4p(-1) molecular states. Using atomic dipole matrix elements to calculate the photoionization intensity of alkali halides has been suggested.
|
|
| 6. |
- Kettunen, J. A., et al.
(författare)
-
Dissociation of As-4 clusters following valence photoionization and 3d core excitation
- 2012
-
Ingår i: Physical Review A (Atomic, Molecular and Optical Physics). - 1050-2947. ; 86:2
-
Tidskriftsartikel (refereegranskat)abstract
- The VUV-induced photofragmentation of As-4 clusters was studied using photoelectron-photoion-coincidence (PEPICO) spectroscopy. The fragmentation pathways subsequent to outer and inner valence photoionization and resonant photoexcitation were studied by examining the cationic production as a function of electron energy. In addition, regular photoelectron spectroscopy and partial ion yield absorption spectroscopy were employed. In order to enhance the weak signal from the inner valence states, resonant core 3d excitation was used in the PEPICO experiment. The fragmentation pathways were inspected with the aid of ab initio and thermochemical calculations. The many-electron effects were found to play a major role in the observed inner valence structure and resulting photofragmentation.
|
|
| 7. |
- Kettunen, J. A., et al.
(författare)
-
Valence electronic structure and photofragmentation of 1,1,1,2-tetrafluoroethane (CF3-CH2F)
- 2012
-
Ingår i: Physical Review A (Atomic, Molecular and Optical Physics). - 1050-2947. ; 85:6
-
Tidskriftsartikel (refereegranskat)abstract
- The electronic structure and fragmentation of the hydrofluorocarbon compound 1,1,1,2-tetrafluoroethane (CF3-CH2F) were studied using spectroscopical methods and quantum chemical calculations. Valence photoelectron spectra and the ionic fragmentation products were recorded with synchrotron radiation in the vacuum ultraviolet (VUV) region. The geometric and electronic structures of the CF3-CH2F molecule were calculated using the complete active space perturbation theory of second order. The calculated vertical ionization energies were used to interpret the experimental photoelectron spectrum. VUV photodissociation of the sample molecule was studied with photoelectron-photoion coincidence spectroscopy. Coincident ion yields are shown for several cations as a function of electron binding energy. The experimental data are discussed in comparison with theory and previous work.
|
|
| 8. |
- Partanen, L., et al.
(författare)
-
2s photoionization and subsequent Auger cascade in atomic Si
- 2010
-
Ingår i: Physical Review A (Atomic, Molecular and Optical Physics). - 1050-2947. ; 81:6
-
Tidskriftsartikel (refereegranskat)abstract
- The 2s photoionization and subsequent Auger transition cascade in atomic Si were studied by means of synchrotron-radiation-induced electron spectroscopy. After the 2s photoionization, the core hole states decay predominantly by a two-step Auger transition cascade into the triply ionized [Ne]nl states. The ionization channels of the 2s core-ionized Si+ atoms to Si3+ ions were observed by measuring the conventional Auger electron spectra of the L-1-L2,3M Coster-Kronig transitions and the L2,3M-MMM Auger transitions. The observed L-1-L2,3M and L2,3M-MMM Auger spectra were analyzed by means of extensive multiconfiguration Dirac-Fock computations. We found that the electron correlation plays a prominent role in the Auger cascade, especially for the final-step Auger L2,3M-MMM spectrum. Additionally, it was seen that the L2,3M-MMM Auger spectrum of Si includes more Auger groups than the isoelectronic L-2,L-3-MMAuger spectrum of Al. Thus, more information on the intermediate ionic states is obtained if they are produced by Auger cascade rather than by direct photoionization.
|
|
| 9. |
- Patanen, M., et al.
(författare)
-
4f photoionization and subsequent Auger decay in atomic Pb: Relativistic effects
- 2011
-
Ingår i: Physical Review A (Atomic, Molecular and Optical Physics). - 1050-2947. ; 83:5
-
Tidskriftsartikel (refereegranskat)abstract
- High-resolution 4f photoelectron and subsequent Auger-electron spectra have been measured from free Pb atoms using synchrotron radiation. The fine structure of the spectra has been investigated theoretically by calculating the energies and intensities for 4f photoionization and Auger decay processes using the multiconfigurational Dirac-Fock approach. The role of the relativistic effects in the ground and singly and doubly ionized states has been studied on the basis of computed results and their comparison with experiment.
|
|
| 10. |
- Patanen, M., et al.
(författare)
-
High-resolution study of K 3p photoabsorption and resonant Auger decay in KF
- 2009
-
Ingår i: Physical Review A (Atomic, Molecular and Optical Physics). - 1050-2947. ; 80:1
-
Tidskriftsartikel (refereegranskat)abstract
- High-resolution (K3p sigma and pi)->sigma absorption spectrum of KF in the photon energy range of 18.2-19.4 eV was measured at the new FINEST beamline branch on the I3 beamline on MAX III. The experimental spectrum is presented and interpreted using nonrelativistic ab initio molecular calculations corrected with perturbation theory treatment to account for spin-orbit interaction. Resonant Auger decay recorded at the strongest resonances is also presented and reproduced by theoretical calculations. Also a brief introduction to the FINEST beamline branch is presented.
|
|
