Photoelectron spectroscopy was used to study the electronic structure in situ in an ultrahigh vacuum before and after the adsorption of sodium atoms on the surface of tungsten oxidized at an oxygen pressure of 1 Torr and a temperature of 950 K. The photoemission spectra from the valence band and the W 4f, O 2s, and Na 2p core states were studied under synchrotron excitation in the photon energy range 80-600 eV. It is found that a tungsten oxide film is formed containing various tungsten oxides with an oxidation state of 6+ to 4+. The deposition of a 1.1 monolayer of sodium atoms on the surface of oxidized tungsten leads to the reduction of the W6+ states to W4+ and the reaction with oxygen in the hydroxyl composition, which is reflected in the change in the spectrum of the W 4f and O 2s core states. It is shown that the cathodoluminescence spectrum is associated with the luminescence of tungsten oxide. Keywords: adsorption, sodium, tungsten oxides, photoelectron spectroscopy, cathodoluminescence.

A mechanism is proposed for the decomposition of molecular clusters of diethylamine (C2H5)2NH on the surface of the NaAux intermetallic compound with the formation of decomposition products desorbed from the surface, including in the form of ions with m/z from 58 to 197, during heating of the intermetallic compound at a rate of 20 K/s. Exposure of the NaAux surface at a temperature of 320 K in diethylamine vapor leads to the formation of molecular clusters on it. Rapid heating of NaAux at a rate of 20 K/s leads to the decay of clusters, desorption, and ionization of the decay products due to the redistribution of internal energy over the degrees of freedom of the cluster. The study of thermal ionization processes during heating of NaAux at a rate of 20 K/s in the temperature range from 600 to 1000 K made it possible to establish that the surface stoichiometry during heating is quasi-stationary, dehydrogenation and ionization of individual diethylamine molecules occur under equilibrium conditions, while for compounds formed in the process of cluster decay, the conditions are not equilibrium. Keywords: thermal ionization, diethylamine, intermetallics, sodium, gold.

The electronic structure of a gold film deposited on W was studied during the adsorption of sodium atoms. An analysis of the photoemission spectra from the valence band and core levels of Au 4f and Na 2p upon synchrotron excitation in the photon energy range of 80-600 eV showed that Na adsorption leads to the formation of NaxAuy intermetallic compounds of various stoichiometry under the Na monolayer. Keywords: adsorption, sodium, gold, intermetallic compound.

The formation of 2D LixAuy semiconductor layers on the surface of gold deposited on a tungsten substrate has been studied. The processes of electron-stimulated desorption of Li atoms in the Li/LixAuy/Au/W system are considered. The presence of two peaks in the kinetic energy distribution of desorbed lithium atoms is shown: a high energy peak at an energy of 0.3 eV and a low energy peak at an energy of 0.11 eV. The high energy peak is associated with the desorption of lithium atoms from the adsorbed lithium layers, and the low energy peak is associated with the LixAuy intermetallic compound. The influence of the number of deposited gold and lithium atoms on the process of formation of 2D semiconductor LixAuy layers is studied. It is shown that the processes of electron-stimulated desorption occur in the Li monolayer and the LixAuy layer closest to it. A model of electron-stimulated desorption of Li atoms in the Li/LixAuy/Au/W system is proposed. Keywords: electron-stimulated desorption, lithium, gold, semiconductor, intermetallic compound.

In a high-vacuum diode, the volt-ampere characteristic of the thermionic emission of Na+ with surface of NaxAu intermetallide. Its hysteresis was found, which is associated with changes in the surface NaxAu caused by the action of an external electric field. In accordance with the Schottky effect, analysis of the current-voltage characteristic and the value of the work function of the NaxAu surface was estimated. Suggested mechanism of thermionic emission of Na+ from the surface of NaxAu. Keywords: intermetallic compound, thermal ionization, Schottky effect.