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The department was created in 1987 on the base of the Computational Physics Laboratory that was a part of Solid-State Spectroscopy Department.   

The researchers of the department have conducted generalization to the relativistic case of the linear muffin-tin orbital method (LMTO) to calculate the relativistic effects within the Dirac formalism, developed a method to calculate the electron-phonon interaction with a full account of relativistic effects, as well as developed a relativistic generalization of the method of dipole transition optical matrix element calculation within the LMTO method.    

Computer software packages have been created for calculation of the energetic structure and physical-and-chemical properties of transition metals, their alloys and compounds on the basis of such quantum mechanical methods as the augmented plane wave method (APW), the relativistic APW method, the LMTO method, the relativistic LMTO method, the x_α-method of scattered waves, the pseudopotential method.

Theoretical research of 5d- and 4d-metals electronic structure has been carried out. Considerable influence of relativistic effects on such characteristics of their electronic structure as dispersion, total and partial densities of states, Fermi surface topology, extreme cross-sections and extreme diameters of the Fermi surface, cyclotron masses, electrons` velocities on the Fermi surface has been determined.    

For the first time the spin-lattice relaxation time (SLRT) in cubic 5d- and 4d-metals has been calculated taking into account the relativistic effects. It has been determined that in their presence the contribution to SLRT of s-symmetry electrons increases essentially. It has been shown that the contribution to SLRT of the quadrupole electric interaction for the nuclei having a different from zero quadrupole moment is not small and in some cases (for instance, in iridium) plays a determining role.    

A wide spectrum of the physical properties of transition metal compounds in which the electron-phonon interaction plays an important part, such as phonon electrical resistance, microcontact spectra, cyclotron-mass anisotropy, temperature behavior of the Grüneisen parameter, has been investigated.  

The optical properties of actinides and 5d- metals in a wide spectral range have been theoretically studied. The electronic structure and anisotropy of the optical properties of transition metals with a hexagonal close-packed crystal lattice and a large variety of transition metal silicides have been theoretically researched. The theoretical explanation of all the features of their experimental spectra has been found.

An analysis of probable causes of the martensitic phase transition in the TiNi and TiPd alloys with unique physical properties, such as the shape memory effect, hyperelasticity, etc. has been conducted. The G.V. Kurdyumov Prize of the NAS of Ukraine has been received for the research results.  

The changes in the electronic structure of crystals caused by the presence of point defects have been investigated within the cluster-fragment model. Nonstoichiometric titanium nitrides and the titanium dihydride that contains scandium and vanadium impurity atoms have been considered.

A program for calculation of the electronic structure of point defects by the LMTO-Green-function method has been created. In particular, using this program the influence of crystal environment on the local electronic structure of Mg atom in the Mg-Al, Mg-Pd, Mg-Cu, Mg-Zn systems has been researched.  

The general relations connecting the energy distribution of the Auger electrons with characteristics of crystal electronic structure have been received. The formulae have been derived to calculate transition probabilities in the Auger electron spectra. It has been shown that orthogonalization of the wave function of an outcoming electron to valence and core states improves considerably the calculation results, certifying the importance of a correct description of the wave function in a spatial domain nearby the atom`s ion core.    

An all-electron full-potential variational method has been developed to build the scattered wave function of a system, consisting of two semi-infinite crystals which are separated with a boundary, thus, giving the opportunity to develop an effective formalism to research the reconstructed surfaces, thin layer films on the surfaces, adsorbates and other structures, where a thorough account of real potential distribution in the near-surface region is essential.  The ab initio theory within this formalism explains the features of the experimental spectra with very high accuracy.

A nature of the polar magneto-optical Kerr effect in the paramagnetic platinum and palladium in an external magnetic field has been theoretically determined. A nature of magneto-optical anisotropy in multilayer Fe/Au films has been determined. It has been shown, that presence of aurum causes high spin polarization and high spin-orbit splitting of d-states of iron, thus determining good magneto-optical properties of these films. Multilayer Co/Pt structures have been researched. In particular, it has been shown that ordering and a crystal lattice type have a strong influence on their magnetic and magneto-optical properties. The compounds that are the most perspective for the development of magneto-optical recording devices have been proposed.

A new method has been developed to describe strong Coulomb correlations within the density functional formalism with a full account of relativistic effects and spin polarization. Using this method the electronic structure and physical-and-chemical properties of mixed-valence compounds, alloys with heavy fermions, transition metal oxides with charge and orbital ordering, and other strongly correlated 4f- and 5f- systems have been studied. Some results of the research were distinguished with the S.I. Pekar Prize of the NAS of Ukraine.

The theory that solved the problem of discrepancy between the theoretically calculated and experimentally received Fermi surface of the Sr₂RhO₄ 4d-oxide has been built. It is shown that to understand the electronic properties of the Sr₂RhO₄ oxide it is necessary along with the Coulomb repulsion to take into account the spin-orbit coupling, which is usually neglected in 4d-oxides. It is found that taking into account the strong Coulomb correlations increases the spin-orbit coupling constant in more than two times. The proposed formalism might be used for description of other systems.

 A nature of the X-ray absorption and X-ray magnetic circular dichroism spectra of a wide class of compounds, in particular, a series of platinum-transition-metal alloys, Heusler alloys, sulfides of transition metals, rare-earth compounds, diluted magnetic semiconductors, a wide spectrum of actinides has been theoretically investigated. A nature of origin of nanostructural clusters, as well as an abnormal behavior of spin polarization in some Heusler alloys has been determined. On the basis of spin spiral studies the ground state of a number of Heusler alloys with noncollinear magnetic structure has been identified.

The exchange interaction in some of high temperature layered superconductors based on iron arsenide, which are characterized by complicated magnetic ordering, has been researched. It is shown that the magnetic interaction in these compounds cannot be described by a simple classical Heisenberg model. Substantial dependence of the exchange interaction on doping has been determined.   

Crucial influence on the properties of some iron chalcogenides and diluted magnetic semiconductors of the spin-orbit coupling, presence of interstitial atoms, the exchange splitting of core levels, and formation of magnetic nanoclusters has been determined. 

It is theoretically shown that in rare-earth compounds the crystal-field split sublevels of 4f-states have dispersion in the k-space, as a result of interaction with valence bands, and even could change the order of their energy arrangement, thus influencing the magnetic properties of these compounds. The result has a direct impact on a general understanding of magnetism and related phenomena, including Kondo effect and quantum criticality.

In the framework of the simplified periodic Anderson model it is shown that in compounds containing rare-earth elements and transition 4d- and 5d-metals the hybridization between strongly localized 4f-states and valence states is significant as a result of considerable spread of 4d- and 5d-orbitals and should be taken into account even for the elements of the end of the rare-earth period. It is shown that in these compounds interaction occurs mainly between the 4f- and valence states with the same wave vector and spin. The interaction strength is determined by dispersion of the valence states and becomes significant where the valence bands approach the Fermi level or cross it. It might be important for orientation dependences of these compounds.

Using the example of EuRh₂Si₂ it is demonstrated that Dirac fermions with the linear dispersion, which is characteristic for the quasiparticles with zero effective mass, and extremely heavy quasiparticles specific for Kondo materials could not only co-exist but strongly interact, and this interaction could take place both at the surface and in the bulk of a crystal. The presence of the linear dispersion is imposed solely by the crystal symmetry, whereas the existence of heavy quasiparticles is caused by the localized nature of the 4f-states.   

1999 – G.V. Kurdyumov Prize of the N.A.S. of Ukraine (V.N. Antonov, Yu.N. Koval and V.V. Nemoshkalenko were awarded for the cycle of research on the martensitic phase transition in the TiNi and TiPd alloys). 

2009 – S.I. Pekar Prize of the N.A.S. of Ukraine (V.N. Antonov as a member of a group of researchers was awarded for the research cycle `Impact of spin-orbit and Coulomb interactions on the properties of electron systems`).  

2012 – A State Prize of Ukraine in the field of science and technology 2011 (V.N. Antonov as a member of a group of researchers was awarded for the research cycle `Quantum effects and structural self-organization in new multifunctional nanomaterials`).