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The xenon 4p photoelectron spectrum and the subsequent 4p-1→(5s,5p)-2 Auger and 4p-1→4d-1(5s,5p)-1 Coster–Kronig spectra have been studied with the aid of a high-resolution experiment and multiconfigurational Dirac–Fock calculations. Strong electron correlation is known to affect drastically the Xe 4p photoelectron spectrum: the 4p1/2 component disappears completely, and the intensity of the 4p3/2 line is redistributed into several close-lying peaks. We have calculated the lifetime widths of the photoelectron peaks, simulated the observed photoelectron and Auger spectra and compared theoretical results with experiment. [Copyright &y& Elsevier]

Abstract: The shake-up probabilities of the outermost electron in inner shell ionization and subsequent Auger decay of alkali atoms have been studied in the sudden approximation model using the wavefunctions obtained with the multiconfiguration Dirac–Fock (MCDF) method. The tendencies of the shake-up probabilities for both the initially excited and the nonexcited configurations were found to be predicted well in the photoionization by the model used. Based on the calculations, the second shake-up during Auger decay was found to receive considerable high intensity. [Copyright &y& Elsevier]

Abstract: The effect of electron correlation has been studied in the case of 4p photoionization of atomic cesium. High resolution synchrotron radiation excited photoelectron spectrum of vapour phase Cs has been measured and compared to the theoretical predictions. The multiconfiguration Dirack–Fock method has been applied in the calculations. [Copyright &y& Elsevier]

Neutral Pb clusters in the size range from a few tens of atoms up to ∼100 atoms are studied using synchrotron-based photoelectron spectroscopy. The electronic structure is seen to differ increasingly from that of the solid when the cluster size decreases. The valence band narrows gradually – down to about one fifth of the solid-state band width at the smallest size of few tens of atoms. Simultaneously the Fermi-edge energy shifts further away from the solid value by more than 2 eV. The Pb 5 d core level binding energy also increases and the spectral features broaden and change in shape. The changes observed for the valence and for the 5 d response energies and shapes are discussed in the context of the metal-to-insulator transition observed earlier in Pb clusters below the critical size of 20–30 atoms/cluster. [ABSTRACT FROM AUTHOR]

Abstract: Binding energy shifts between atomic and solid phases for transition metals Cr, Mn, Fe, Co, and Ni have been obtained for 3p subshells from simultaneously recorded atomic vapor and solid state spectra. This experimental technique provides higher accuracy in comparison to separate measurements and allows direct determination of the shifts. The observed shift values are compared to values obtained using the semiempirical Born–Haber cycle method and the peak structures of the solid state photoelectron spectra are compared to atomic 3p spectra. The binding energy shift of Cr is found to be much smaller than that of the other studied elements. [Copyright &y& Elsevier]

Abstract: Binding energy shifts between atomic and solid states have been observed with improved accuracy for Au 4f and Ag 3d core levels applying a simultaneous measurement method. Also the 3d photoelectron spectrum and binding energies of free Ag atoms have been observed for the first time. New values determined as free atom to bulk solid shifts deviate considerably from previous estimate for Au but agree reasonably well for Ag. The valence bands were also found to shift rather accurately by the same amount as the core levels. [Copyright &y& Elsevier]

Abstract: Molecular LiCl and Li2Cl2 have been studied in the vapor phase with valence photoelectron and photoelectron–photoion coincidence spectroscopies. These two techniques determine the binding energies in fundamentally different ways. Binding energies obtained from photoelectron spectra are usually taken as the vertical ionization energies of the corresponding electronic states. In cases with several overlapping bands, corresponding to different electronic states, the coincidence measurement can separate the bands if the respective final states fragment differently. This applies well to the monomer case. To facilitate the determination of state-specific ionization energies in the dimeric molecule, a theoretical Franck–Condon analysis has been carried out. Moreover, ab initio coupled-cluster and density-functional-theory calculations have been used to analyze the fragmentation pattern based on asymptotic dissociation energies. The fragmentation pattern is largely common to all the accessible valence-ionized states of the dimer, consistent with rapid conversion to the ionic ground state before fragmentation. However, the highest-lying state of Li2Cl2 +, 2 A g , shows enhanced propensity for Li+ as dissociation product. [Copyright &y& Elsevier]

Abstract: Binding energy shifts between free and solid state atoms for K 2p and Rb 3d photolines have been determined by measuring the vapor and solid state spectra simultaneously in similar experimental conditions applying synchrotron radiation excited photoelectron spectroscopy. This method has the important benefit that the work function is not needed to correct for different reference energy levels, therefore much more accurate values for binding energy shifts are obtained. [Copyright &y& Elsevier]

Abstract: High resolution 4f photoelectron spectra have been measured from Au, Pb, and Bi vapors using synchrotron radiation. New accurate binding energy values are found to deviate more than 0.3eV for Au from the previous results demonstrating the need for new precise values, e.g. for chemical shift and cluster studies. For Bi both atomic and diatomic lines have been observed simultaneously, molecular lines at 0.96eV lower binding energies. Fine structure splitting created by the coupling of the 4f core hole to the open 6p shell has been found to manifest itself in this high resolution experiment as slightly different line widths for 4f spin components. The fine structure has been investigated also theoretically by calculating the 4f photoionization energies, intensities, and lifetimes using the multiconfigurational Dirac–Fock approach. [Copyright &y& Elsevier]

Abstract: The KLL Auger electron spectra of atomic sodium and magnesium have been recorded with high resolution applying electron impact. Nearly all spectral features have been identified with the help of Hartree–Fock calculations. A comparison of the behaviour of shake probabilities and KLL Auger linewidths for elements with has been carried out. [Copyright &y& Elsevier]

Abstract: The valence photoelectron spectrum has been measured for molecular KBr. Experimental energies of the main and satellite structures have been compared with the results of ab initio calculations based on molecular orbital theory including configuration and multiconfiguration interaction approaches. Comparison between the experimental KBr spectrum and previously reported Kr valence photoelectron spectrum has also been performed in order to find out if electron correlation is of the same importance in the valence ionized state of KBr as in the corresponding state of Kr. [Copyright &y& Elsevier]

Abstract: The Xe and resonant Auger transitions have been studied both theoretically and experimentally. High resolution resonant Auger spectra have been recoded with different photon bandwidths which have enabled to separate the first step Auger transition from the overlapping second step transitions. Theoretical calculations using multi-configuration Dirac–Fock approach with different configuration expansions were carried out, compared to each other and to the experiment. The calculations with the largest basis set were found to reproduce the distribution of the intensity to the main and satellite lines in both the and Auger groups reasonably well, and to predict the structure of the main lines very well. [Copyright &y& Elsevier]

Abstract: The development of the fine structure of the and ( in Na, in K, in Rb, in Cs) configurations of alkali atoms ions from LS-coupling to jK-coupling has been studied by comparing the experimental photoelectron spectra with the results obtained with analytical LS-coupling and jK-coupling models. [Copyright &y& Elsevier]

Abstract: An electron energy loss spectrometer for measuring vapor phase and gaseous samples is described. Electron energy losses of krypton and xenon due to excitations of valence electrons are presented. The energies of the loss peaks are assigned and compared with existing data. Relative intensities of transitions in different scattering angles are presented. Using the data obtained from these results the performance of the spectrometer is evaluated. Future plans, modifications and improvements are discussed. [Copyright &y& Elsevier]

Abstract: A new electron-energy-resolved electron-ion coincidence setup was developed based on the Scienta SES-100 hemispherical electron analyzer and a Wiley–McLaren type ion TOF spectrometer. With this setup, an electron-ion coincidence study of gas-phase acetonitrile () was performed using synchrotron radiation. The fragmentation patterns in coincidence with resonant Auger electrons were recorded, following N 1s core excitations to the molecular orbital of the character. Also the dissociation of doubly charged molecular ions produced after normal Auger decay of N core-hole states was investigated from PEPICO and PEPIPICO maps. Kinetic energy releases in some reactions were determined with the aid of Monte-Carlo modelling. [Copyright &y& Elsevier]

Abstract: Angular distributions of the spin–orbit split components and their branching ratios have been studied experimentally and theoretically for the 3d photoelectrons of Kr and 4d photoelectrons of Xe. The focus was on the electron dynamics near the ionization threshold of each spin–orbit split component and its behaviour as a function of Z in passing from Kr to Xe. The experimental spectra were measured with high photon and electron energy resolutions with photon energies at about 3–12 eV above the and thresholds for Kr and at about 5–12 eV above the Xe and thresholds. Experimental results for the angular distribution parameters have been compared with theoretical values obtained with relativistic Dirac–Fock method and results from independent particle approximation with a modified Hartree potential [A. Derevianko, W. Johnson, K. Cheng, Atom. Data Nucl. Data Tables 73 (1999) 153]. The branching ratios were compared with theoretical predictions from Dirac–Fock and relativistic random-phase approximation [K. Cheng, W. Johnson, Phys. Rev. A 28 (1983) 2820]. [Copyright &y& Elsevier]

Abstract: Photoionisation and photofragmentation of molecular rubidium halides following photoexcitation in the vacuum ultraviolet region are investigated. For this purpose total and partial ion yield spectra are measured from the vapours of RbF, RbCl, RbBr and RbI. Two different decay channels – spectator and participator type – are studied in different rubidium halide molecules. It is demonstrated that the opening of the spectator channel takes place at different excitation energies, depending on the halide atom in the molecule. [Copyright &y& Elsevier]

Abstract: We study numerical deconvolution as a means to improve spectral resolution using the resonant Auger spectra following the 1s 3p excitation in Ne as an example. By analyzing the asymmetry parameters of the Auger electron emission we show that intensity ratios are not affected by deconvolution. [Copyright &y& Elsevier]