Theoretical studies of electronic structure and magnetic properties

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Staff of Research Group

Grechnev G.E.  CV file pdf 46 kB e-mail: grechnev@ilt.kharkov.ua	Head of group Doctor of Sciences,  Senior researcher
Baranovskiy A.E.	Junior Research Fellow
Logosha A.V.	Junior Research Fellow

Main directions of studies

First-principles calculations of the electronic structure and magnetic properties of metallic systems and semiconductors.

Theoretical studies of magnetic structure of solids.

Ab initio calculations of equations of states and thermodynamical properties of solids.

Analysis of hybridisation effects in their relation with stability,
elastic, and magnetic properties.
 

Main principal results, recently obtained:

Giant orbital diamagnetism was discovered in metals and compounds, related to topological FS transitions.

Anisotropic magnetic susceptibility of HCP transition metals was calculated ab initio.

Theoretically studied anisotropic magnetic properties of HCP iron in the Earth inner core, and its possible relation to the seismic anisotropy of Earth.

Theoretical investigations of electronic structure, stability, magnetic and electro-chemical properties of potential lithium batteries based on Mn oxides.

Analysis of elastic properties of super hard materials, such as transition metals dioxides and dodecaborides.

The study of nature of strong magnetovolume effects in highly enhanced itinerant paramagnets and weak ferromagnets, based on 3d-elements, rare-earths and actinides.

Detailed calculations of electronic structures, elastic and magnetic properties of rare-earth hexaborides and dodecaborides have been performed.
 

Theoretical methods:

• We use modern methods of computational and theoretical solid state physics for ab initio calculations of band structures within Density Functional Theory, including linearized muffin-tin method in atomic sphere approximation LMTO-ASA, and a full potential FP-LMTO method.
• Also the augmented spherical wave method (ASW) and ab initio pseudopotentials were employed.
• LMTO-ASA and FP-LMTO are modified to take into account the effect of external magnetic fields in the framework of ab initio DFT calculations.

 

Main publications of last years

G. E. Grechnev, N. V. Savchenko, I. V. Svechkarev, M. J. G. Lee, J. M. Perz. Conduction electron g-factors in the noble metals. Phys. Rev. B. 39, 9865 (1989).

G. E. Grechnev, J. Kubler, I. V. Svechkarev. Itinerant magnetism and electronic properties of FeGe₂, J.Phys.: Condens. Matter, 3, 7199 (1991).

G. E. Grechnev, T. Jarlborg, A. S. Panfilov, M. Peter, I. V. Svechkarev. Effect of pressure on the electronic structure and magnetic susceptibility of FeSi. Solid State Commun. 91, 835 (1994).

P. E. Brommer, G. E. Grechnev, J. J. M. Franse, A. S. Panfilov, Yu. Ya. Pushkar, I. V. Svechkarev. Pressure effect on the enhanced itinerant paramagnetism of Ni₃Al and TiCo compounds. J. Phys.: Condens. Matter, 7, 3173 (1995).

G. E. Grechnev, A. S. Panfilov, I. V.Svechkarev, K. H. J. Buschow, A. Czopnik. Conduction electron mediated exchange coupling in heavy rare earth metal compounds RM and RM₃. J. Alloys and Compounds, 226, 107 (1995).

G. E. Grechnev, A. S. Panfilov, I. V. Svechkarev. Pressure effect on the enhanced paramagnetism of MnSi. J. Magn. and Magn. Mater. 157, 711 (1996).

K. H. J. Buschow, G. E. Grechnev, Anders Hjelm, Y.Kasamatsu, A. S. Panlov, I. V. Svechkarev. Exchange coupling in GdM compounds. J. Alloys and Compounds, 244, 113 (1996).

G. E. Grechnev, A. S. Panfilov, I. V. Svechkarev, P. E. Brommer, J. J. M. Franse, F. E. Kayzel. Pressure effect on electronic structure and magnetic properties of RNi₅. Physica B, 237, 532 (1997).

G. E. Grechnev, N. V. Ushakova, G. G. Kvachantiradze, P. D. Kervalishvili, K. S. Khorebov. Electronic structure of diborides of 3d metals. Low Temp. Phys, 23, 217 (1997).

A. S. Panfilov, I. V.Svechkarev, A. Delin, O. Eriksson, B. Johansson, J. M. Wills. Magnetovolume effect in UGa₃. J. Magn. Magn. Mater., 192, 137 (1999).

G. E. Grechnev, A. S. Panfilov, I. V. Svechkarev, D. Kaczorowski, A. Hackemer, O. Eriksson. Magnetovolume effect in UX₃ (X = Si, Ge, and Ga) compounds, Materials Science Forum, 373, 653 (2001).

G. E. Grechnev, R. Ahuja, B. Johansson, O. Eriksson. Electronic structure, magnetic, and cohesive properties of Li_xMn₂O₄ : Theory. Phys. Rev. B 65, 174408 (2002).

H. W. Hugosson, G. E. Grechnev, R. Ahuja, U. Helmersson, L. Sa, O. Eriksson.Stabilization of potential superhard RuO₂  phases: a theoretical study, Phys. Rev. B 66, 174111 (2002).

A. E. Baranovskiy, G. E. Grechnev, G. P. Mikitik, I. V. Svechkarev. Anomalous diamagnetism in the intermetallic compounds CaPb₃  and YbPb₃ , Low Temp. Phys. 29, 473 (2003).

G. E. Grechnev, R. Ahuja, B. Johansson, O. Eriksson. Electronic structure and magnetic properties of lithium manganese spinels, J. Magn. Magn. Mater. 258, 287 (2003).

A. E. Baranovskiy, G. E. Grechnev, I. V. Svechkarev, O. Eriksson, Electronic structure and magnetic properties of GdM₂  compounds J. Magn. Magn. Mater. 258, 520 (2003).

G. E. Grechnev, R. Ahuja, O. Eriksson. Magnetic susceptibility of hcp iron and the seismic anisotropy of Earth's inner core, Phys. Rev. B 68, 64414 (2003).

G. E. Grechnev, R. Ahuja, Jinghua Guo, O. Eriksson. Electronic structure and optical spectra of novel rechargeable lithium batteries. Proceedings of the SPIE - The International Society for Optical Engineering, 5507,  44 (2003).

G. E. Grechnev, Electronic structure and magnetic properties of LiM₂O₄ spinels, Proceedings Russian Acad. Sci. (physics) 68, 674 (2004).

A. E. Baranovskiy, G. E. Grechnev, I. V. Svechkarev, A. Czopnik. Peculiarites of diamagnetic susceptibility in RM₃  compounds and alloys. Czechoslovak Journal of Physics 54, 355 (2004).

G. E. Grechnev, A. E. Baranovskiy, A. V. Logosha, N. Yu. Shitsevalova, I. V. Svechkarev, O. Eriksson. Electronic structure and magnetic properties of semiconducting and semimetallic borides, Physica Status Solidi C 3, 229 (2006).

A. E. Baranovskiy, G. E. Grechnev, I. V. Svechkarev, Electronic spectrum peculiarities and anomalous magnetism in YbPb₃, YbSn₃, CaPb₃ and CaSn₃ compounds. Low Temp. Phys. 32, N8/9, 1119 (2006)

G. Kontrym-Sznajd, M. Samsel-Czekala, G.E. Grechnev, H. Sormann. On the reliability of linear band structure methods. "Los-Alamos e-print",USA, arXiv:Cond-mat/0709.09

G. E. Grechnev, A. V. Logosha,  I. V. Svechkarev, A. G. Kuchin, Yu. A. Kulikov, P. A. Korzhavyi, and  O. Eriksson. Electronic structure and magnetic properties of RNi_5-xCu_x  alloys (R = Y, La, Ce). Low Temp. Phys., 32, 1140 (2006).

G.E. Grechnev, A.E. Baranovskiy, A.V. Logosha, A.S. Panfilov, V.D. Fil, T.V. Ignatova, N.Yu. Shitsevalova, O. Eriksson. Pressure effect on electronic structure and magnetic properties of MB₆ and MB₁₂ borides. High Pressure Physics and Technology, 16, N4, 110-114 (2006).

G.E. Grechnev, A.V. Logosha, A.S. Panfilov, I.V. Svechkarev, O. Musil, P. Svoboda. Magnetovolume effect in Ce(Ni_1-xCu_x)₅ alloys. Los-Alamos e-print",USA, arXiv:Cond-mat/0611325 (2006)..

A. E. Baranovskiy, G. E. Grechnev, V. D. Fil, T. V. Ignatova, A. V. Logosha, A. S. Panfilov, I. V. Svechkarev, N. Y. Shitsevalova, V. B. Filippov, O. Eriksson. Electronic structure, bulk and magnetic properties of MB₆ and MB₁₂ borides. Journal of Alloys and Compounds, 442, N2, 228-230 (2007).

G. Kontrym-Sznajd, M. Samsel-Czekala, G. E. Grechnev, H. Sormann. Fermi surface of ErGa_3. Physica Status Solidi C, 4, N9, 3879-3882 (2007).

G.E. Grechnev, A.V. Logosha, A.S. Panfilov, I.V. Svechkarev, O. Musil, P. Svoboda. Magnetovolume effect in Ce(Ni_1-xCu_x)₅ alloys.Hiigh Pressure Physics and Technology, 17, N 1, 59-66 (2007).

A.E. Baranovskiy, G.E. Grechnev, A.S. Panfilov, I.V. Svechkarev, O. Zogal, A. Czopnik, A. Hackemer, Anomalous magnetism of YbPb_3: the effect of pressure. Low Temp. Phys. 33, 1028 (2007). 

G. Kontrym-Sznajd, M. Samsel-Czekala, G.E. Grechnev, H. Sormann. On the reliability of linear band structure methods. "Los-Alamos e-print",USA, arXiv:Cond-mat/0709.09

G.E. Grechnev, A.E. Baranovskiy, V.D. Fil, T.V. Ignatova, I.G. Kolobov, A.V. Logosha, N.Yu. Shitsevalova, V.B. Filippov, O. Eriksson. Electronic structure and bulk properties of MB₆ and MB₁₂ borides. Low Temp. Phys. 34, N11 (2008), accepted..
 

International cooperation

• Department of Physics, Uppsala University, Sweden
• Institute of Metal Physics of the Ural Division of the Russian Academy of Sciences
• Institute of Low Temperature and Structure Research, Polish Academy of Sciences, Wroclaw, Poland
• Institute of Experimental Physics, Slovak Academy of Sciences, Kosice, Slovakia
• Hahn Meitner Institut, Berlin, Germany
• General Physics Institute, Russian Academy of Sciences, Moscow, Russia
• FRANTSEVICH Institute for Problems of Materials Science, Ukrainian National Academy of Sciences, Kiev, Ukraine