Department Of Nanostructures Physics has its origin from The Department Of Spectroscopy of Solid Surface, which was created in 1995 as successor of The Laboratory Of Spectroscopy of Solid Surface. From 1995 to 2011 department headed by Dr. Sci. in Physics and Mathematics, professor, academician of NAS of Ukraine Shpak Anatoliy Petrovich. Since 2012 the department headed by Dr. Sci. in Physics and Mathematics, professor Vladimir Karbovskii. In 2015, taking into account the scientific orientation of performed science topics and the developments of the scientific school of academician A. P. Shpak, the Department Of Spectroscopy of Solid Surface was renamed as Department Of Nanostructures Physics.
Period from 1985 to 1999
Clusters calculation method in Xa-SW approach, was enabled substantial progress in the explanation of the mutual effect of the two cooperative phenomena - local atomic and spin ordering in amorphous metal alloys (AMA) Was improved. It was developed a powerful computer framework, based on the IBM PC, allowed to carry out a control of the experiment and mathematical processing of the results, as well as complex theoretical calculations of the electronic structure (A. N. Yaresko).
A number of fundamental issues of electronic structure of matter being in a cluster state were resolved. It was revealed the physical nature of cluster formation process in the AMA and the impact of various factors on this process (type of transition metal, metalloid, etc.). As a result of these investigations in Ukraine created a group to study the structure and properties of condensed matter by X-ray spectroscopy method – EXAFS (V. L. Karbovskii, A.V. Melezhik).
A complex of studies of metal-oxide clusters of chromium and iron, deposited on the surface of the highly dispersed matrix was performed. It is shown that the surface of the dispersed magnesium oxide is possible stabilization of Fe(VI), tetrahedrally coordinated by oxygen atoms (I. V. Pluto).
A quantitative layer-by-layer analysis of the composition of amorphous metal alloys of SM-SM –SM-Me was carried out. The mechanisms of surface segregation of metalloid in AMA were established (S. I. Latypov, A. G. Dmitriev).
The technique of reconstruction of atomic structure of disordered (amorphous, liquid) system for a given pair correlation function was developed. In disordered metallic systems the presence of clusters with packaging homologically associated with the structure of the corresponding crystalline phases was detected. Cluster structure and observed temperature transformations in amorphous and liquid materials was described in the frame of the hole approach (A. B. Melnik).
The effect of structural changes on the electronic structure of phosphate cluster compounds based on 3d-metals such as: MIMIV(PO4)3, MIMIIIP2O7, MITiOPO4, where MI - alkali metal and MIII, MIV - transition metals was investigated. The results allowed developing specific recommendations for targeted synthesis of complex phosphates, used as laser glasses, and having high spectral-luminescent and generation parameters, as well as on the use of such materials as fillers in compact chemical power sources (I. P. Nagibin, A. B. Podenezhko, A. M. Korduban).
Based on the fundamental studies of atomic and electronic structure of low-dimensional systems A. P. Shpak and co-workers developed the physico-chemical basis of a original direction - the Cluster Materials Science. It uses modern arsenal of experimental techniques: X-ray and X-ray electron spectroscopies, electron microscopy and electron diffraction, resonance methods (NMR, EPR, M?ssbauer), EXAFS-spectroscopy, highly informative methods of structural analysis. As part of the unified cluster models were performed quantum-mechanical calculations of the electronic structure of cluster materials. This significantly upgraded and developed cluster method Xa-scattered waves, LMTO calculation method of the band structure, LMTO Green's function method. Using a unique set of experimental and theoretical methods allowed to obtain detailed information about the structural features, energy spectrum the valence electrons, the nature of interatomic interactions and on the basis of these results to construct a physical model of the atomic and electronic structure of a large class of new materials: amorphous systems, clusters on the surface, metal phosphate materials, metal clusters.
The obtained results for highly dispersed materials actively used in the development of methods and technologies for the synthesis of catalysts, selective sorbents, effective absorbers of electromagnetic radiation. Based in the physical chemistry of amorphous systems research were offered new technologies of amorphous ribbons with high magnetic characteristics, high corrosion resistance.
For series of works in this area, A. P. Shpak, among other authors in 1992 was awarded the State Prize of Ukraine in the field of science and technology.
Period from 2000 to 2015
Created computer framework based on a cluster of modern computers, allowing to carry out theoretical calculations of physical and chemical properties and electronic structure. Was used wide range of quantum mechanical calculations in within a solid-state approach (the full-LAPW + LO, with basis pseudopotential plane waves LMTO and the PAW-methods) and cluster method X?-SW. The comprehensive approach of the simultaneous use of both experimental and theoretical methods allow to obtain detailed information about the physical and chemical properties, the nature of the interatomic interaction and on their basis to construct physical models of the atomic and electronic structure of a large class of new materials, such as apatite-like materials and metal clusters.
For the first time was carried out first-principles calculations of mechanical, dielectric and structural properties of apatite-like compounds. The spatial distribution of the valence electron density for a variety of apatite Me10(ZO4)6X2, where Me = Ca, Cd, Z = P, V, As, X = F, Cl, Br, OH was described. It was found that the speed of sound along the axis of the sixth order fluoro-, chloro- and calcium hydroxyapatite higher than in a plane perpendicular to it. Dielectric constant tensor of the effective Born charges and evaluated the piezoelectric properties of apatite were calculated (A. P. Soroka, V. L. Karbovskii). Based on these data the technique of selective isolation of radionuclides from aqueous solutions (N. A. Kurgan, V. L. Karbovskii).
Research in the area of apatite science has led to the development of a number of practical applications with use of apatite-based compounds. Was established the high sorption capacity for H2O and 90Sr nanosized crystals of apatite caused by a small particle size, and non-stoichiometric composition. The sorption of 90Sr at nanodispersed calcium hydroxylapatite, followed by his transfer to the crystalline state at 650 °C leads to a 30-fold reduction of desorption rate of isotope from apatite structure. Based on these data the technique of selective isolation of radionuclides from aqueous solutions (N. A. Kurgan, V. L. Karbovskii).
The unique results of investigations structure and properties of the mineral component of human bone tissue were obtained. Were developed and implemented in the surgical practice medications based on calcium hydroxyapatite, that enable to obtain implants biocompatible with human bones. In this direction intensively developed and applied resonance methods for studying solids. It was established number of peculiarities between the parameters of the NMR spectra of nanosized apatite of biogenic and synthetic origin (J. A. Zagorodnii, V. L. Karbovskii).
Scientific activities of the group led by Dr. Sci. in Physics and Mathematics, academician of Academy of Technological Sciences of Ukraine I. V. Plyuto focused on two main directions. The first direction is the development of theoretical and experimental fundamentals of X-ray photoelectron spectroscopy as an analytic technique of nanochemistry (results of the work are summarized in the monograph - I. V. Plyuto, A. P. Shpak. Characterization of disperse heterogeneous systems by X-ray photoelectron spectroscopy. – Kiev: Naukova Dumka, 2000). The second direction of scientific activity is development and introduction of a new method of spectral diagnostics of bionanosistems and eye tissues in real-time the infrared transillumination ophthalmoscopy (Theoretical and experimental bases of the method set out in the work I.V.Plyuto, A.P.Shpak. Infrared transscleral ophthalmoscopy: physical and technological aspects of the method. - Kiev: IMP NASU 2005, rus.). Was published a first edition of the atlas (I.V.Plyuto. Atlas of the spectral diagnostics of internal eye membranes using transillumination technology. Issue 1.- Kiev, VVP, 2008). National priority in this area recorded at the Congress of Ophthalmologists EURETINA (Monte Carlo, Monaco) and the World Exhibition of technologies (Hanover 2011), where the IRIS system was presented at the stand of Ukraine.
The original technology of synthesis of nanopowders of refractory metals and their oxides using electric explosion of conductors was developed. The technology of nano-dispersed coatings directional electrical explosion using electrothermal accelerator was created. Nanodispersed coating of tungsten on copper external anode of microplasmatron with high electroerosive performance was obtained. The technology of forming continuous dispersed mesoporous films based on nano TiO2 was developed. The technology of formation of nano-dispersed coverages from nanopowders of metals and their oxides using microplasmatron was evolved (O. M. Korduban).
In cooperation with the Department of structure of liquid and amorphous metals were resolved a number of fundamental questions regarding the electronic structure of matter in the cluster state. The physical nature of the cluster formation process in AMA and effects of various factors on this process (such as a type transition metal, metalloid, etc.) was revealed. In addition to traditional X-ray diffraction methods EXAFS- and tunneling spectroscopy were used as well (O. G. Ilinskii, V. L. Karbovskii).
A special place in the works of the department was given to the study of the interaction of metal nanoparticles with biological objects. The main regularities of formation of chemical bonds of plant viruses with the surface of semiconductor single crystals, as well as changes in the virions conformation after deposition. It is shown that the adsorption of tobacco mosaic virus virions is accompanied by mainly monolayer formation of ordered structures on the surface and changes the virion height, while as the adsorption of alfalfa mosaic virus accompanied by the formation of disordered virions structures. It was found that the change in virions height depends on the number of negatively charged amino acid residues on the outer surface of the capsid (T. A. Kornijuk, V. L. Karbovskii).
By V. L. Karbovskii with students was created original technology of thermal synthesis of monolayer metal structures on the surface of solids. It was shown that the processes of self-organization of nanostructures on surfaces of solids are determined by physico-chemical parameters of surface as well as thermal deposition conditions.
Division comprises 17 employees, including 2 Doctors of Science and 5 PhDs. Over the past 10 years in the department defended 2 doctoral and four PhD theses.
International scientific communications of department are expanding. Currently being performed collaborative projects with foreign physical and technical centers in Russia, the Republic of Belarus, Germany and Poland.
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