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The integral mixing enthalpy of liquid Li-Pb alloys was measured with the use of the calorimetric technique. The experimental studies involved measurements at different temperatures: 817, 923, 1021 and 1023 K in the entire concentration range. The thermodynamic optimization was performed basing on the obtained results and the available literature data. The description of the excess Gibbs energy of temperature and composition was proposed with the use of a new model, which connects the polynomial and associated modelling. The obtained molar mixing enthalpy changes, excess Gibbs energy, and the molar excess entropy values are negative in the entire concentration range. Moreover, the existence of Li4Pb and LiPb associates in the liquid solutions was found, according to the analysis of the partial concentration structure factors (Scc(0)) and short range order (SRO) parameters.

The complex formation model is used with a view to study the effect of complex or compound formation on thermodynamic and surface properties of Hg–Pb and Hg–In liquid amalgams through the calculation of free energy of mixing (GM), heat of mixing (HM), entropy of mixing (SM), microscopic functions (concentration fluctuations Scc(o) and the Warren Cowley short range order parameter (α1)) for whole concentration range at compound forming temperatures of 600 K and 298.15 K, respectively. The mixing behaviour of these alloys has been examined by computing ratio of diffusion coefficients (DM/Did) which shows that the maximum deviation from ideal values (DM/Did = 1) occurs around compound forming concentration. Surface properties have also been analysed using two different approaches which reveal that with the addition of Pb in Hg–Pb alloy, surface tension of alloy decreases and Pb atoms tend to segregate at the surface, while surface tension of Hg–In alloy increases with the addition of In. Increase in surface tension value in between 0.5 and 0.8 atomic fractions of In supports compound formation in this range of concentration, which is also supported by the results of thermodynamic properties. The results also show that the ordering energies are temperature dependent and thermodynamic parameters are in reasonable agreement with the experimental results. The analysis of these properties suggests the presence of HgPb2 and HgIn complexes in liquid Hg–Pb and Hg–In alloys, respectively.

The mixing behaviour of cadmium–zinc binary liquid alloys have been examined by computing thermodynamic properties, such as free energy of mixing (GM), heat of mixing (HM), entropy of mixing (SM), activity (ai) and microscopic functions, such as concentration fluctuations in long wavelength limit (Scc(0)), Warren–Cowley short range order parameter (α1) and ratio of diffusion coefficients of the alloys at 800 K using statistical model in the framework of quasi-chemical approximation. Surface properties have also been analysed using four different approaches. The theoretical study reveals that the ordering energy parameters are temperature dependent and all the observed thermodynamic parameters are in reasonable agreement with the observed values. The Cd–Zn liquid alloys at 800 K represent a segregating system with segregation of Cd-atoms at the surface. The values of surface tension obtained from different approaches have been found to be comparable with each other.

Structure of Cu1−xPbx (x=0, 0.025, 0.05, 0.075, 0.1, 0.125) molten alloys has been studied by means of X-ray diffraction method. Structural parameters obtained from structure factors (SF) and radial distribution functions were analyzed. Partial structure factors were calculated by using Reverse Monte-Carlo method. It is shown that tendency to preferred interaction of atoms of the same kind grows with increasing of lead content.

The structure of Cu0.005Bi0.995 eutectic alloy doped with Ni-powder of 3 μm size (5:10 and 15 at.% Ni) has been studied in liquid state by means of an X-ray scattering method. It is shown that Ni-particles are soluted in eutectic melt whose atomic distribution reveals the increase of tendency to formation of chemical short range order upon soluting.

Our recent studies related to the properties of alcohol/water mixtures, show the occurrence of some kind of molecular aggregation in the water rich region of composition beyond a threshold alcohol concentration x 2 ∗ . The observed behaviour suggests that for x 2 2 ∗ the alcohol molecules are essentially dispersed and surrounded by “water cages” where the short range order and microdynamic of water molecules are changed with respect to those of pure water. Alcohol molecules are in mutual contact at higher concentration, only, when almost all water is involved in hydration shells of alcohol molecules. In addition, these studies show that the stabilisation of micellar structure and nucleic acids conformation in water/alcohol mixtures is closely linked to the properties and anomalous behaviour of the solvent systems. Accordingly, these results support the hypothesis that the dominant mechanism by which an alcohol affects these processes is through its effect on the structure of water. The main results of these investigations are reviewed and discussed in this paper.

Dielectric investigations on two oriented swallow—tailed compounds and a mixture of a swallow—tailed and a laterally substituted substance were carried out. The results are discussed from the point of view of a change in the short range order due to geometrical variation of the molecular shape.