[en] An attempt is made to systematize the data on the relaxation characteristics of liquid alkali metals (Li, Na, and K), which were investigated based on neutron-scattering data with the application of the two-time memory function formalism.

[en] A technique is proposed for determining the impurity concentration in liquid metal-impurity systems. This technique does not require special measurements or geometry: information about the impurity concentration can be obtained directly from the data collected during the diffraction experiment. The impurity concentrations in a lead melt with a potassium impurity and in a sodium melt with a lead impurity are determined.

[en] The microstructure of Li-N melts with nitrogen impurity contents of 1.3 and 3.5 at % has been investigated by neutron diffraction. The main microstructural characteristic of the material (total structure factor) and the partial structure factors of the melt components and the radial distribution functions of particles have been obtained. It is established that there is no prepeak in the structure factor of Li-N melts, which indicates the existence of clusters of a certain size in the melt. Analysis of the partial structural characteristics suggests the existence of nitrogen impurity in Li-N melts in the form of lithium nitride Li₃N

[en] The frequency spectra of vibrations of Li atoms at temperatures of 22, 227, 397, and 557 deg. C and the lithium-hydrogen melt (98 at % ⁷Li, 2 at % H) at 557 deg. C have been obtained from the experimental neutron inelastic scattering data. On the basis of the frequency spectra, the temperature dependences of the mean-square displacement of Li atoms, the mean-square amplitudes of atomic vibrations, and the velocity autocorrelation function of atoms have been calculated. The speed of sound in liquid lithium has been estimated within the Debye model. The frequency spectra of lithium-hydrogen melt and solid lithium hydride are compared. A generalized frequency spectrum of vibrations of hydrogen atoms in lithium-hydrogen melt is obtained

[en] The dynamic structure factor S(Q,ω) of liquid gallium (l-Ga) is investigated by means of the slow neutron inelastic scattering on a high resolution time-of-flight spectrometer at IBR-2 reactor of JINR - Dubna. New experimental data are obtained in the range of the low Q wave vector transfers. Sound - wave peaks are clearly visible in S(Q,ω) and the results for the dispersion curves are presented. There is a strong correlation between the anomalous static structure factor S(Q) and the well defined excitations at finite frequencies revealed by the dynamic structure factor S(Q,ω). (authors)

[en] From the experimental data on inelastic neutron scattering the frequency spectrum of lithium atomic vibrations is extracted at the temperature of 22, 227, 397 and 557 deg. C. The frequency spectrum for lithium-hydrogen melt (98 at.% Li⁷, 2 at.% H) has been obtained at 557 deg. C. Based on the frequency spectrum, the temperature dependencies of the mean-square of the lithium atoms displacements in time, the mean-square amplitude of atomic vibrations, velocity autocorrelation function of atoms are calculated. A generalized frequency spectrum of hydrogen atomic vibrations in lithium-hydrogen melt is obtained

[en] The quasielastic neutron scattering experiments on liquid lithium (at 500 K and 830 K) and lithium-hydrogen melt (99 at.% Li⁷ and 1 at.% H at 830 K) were performed with the DIN-2PI time-of-flight spectrometer (FLNP, JINR, Dubna). The characteristics of the diffusion mobility for particles comprising the liquids studied are extracted from the experimental results and analyzed with the help of the phenomenological and theoretical models. The self-diffusion coefficient in liquid lithium obtained for both temperatures is in the agreement with the one known in literature. The questions connected to hydrogen diffusion in the liquid lithium are discussed

[en] Neutron quasielastic scattering experiments on liquid lithium (at 500 and 830 K) and a lithium-hydrogen melt (99 at.% Li⁷ and 1 at.% H at 830 K) have been performed. The characteristics of the diffusion mobility for lithium and hydrogen atoms have been extracted from the experimental results and analyzed with the use of phenomenological and theoretical models. The self-diffusion coefficient in liquid lithium obtained for both temperatures is in agreement with values in the literature. The mechanism of hydrogen diffusion mobility in liquid lithium is discussed. It has been concluded that the hydrogen in the liquid lithium exists and diffuses in the form of the hydride LiH