Research area: Lattice Dynamics, phonons and
other quasiparticle excitations in solids:
 Propagation and localization of vibrations in illordered crystals,
heterogeneous structures and disordered systems
 Vibrational characteristics of crystals with complex defects;
 Dynamics of complex crystal lattices, strongly anisotropic crystal
structures, and quasilowdimensional lattices.
 Quasiparticle spectra of nanosystems.
Main achievements:
 The main distinctive peculiarities of phonon spectra of strongly
anisotropic layered and chain crystals were determined and systemized (with
E.S. Syrkin); the effect of these peculiarities on the behaviour of
oscillatory thermodynamics characteristics of this kind of compositions was
studied, in particular, there was defined a microscopic theory of the
socalled "membrane effect".
 Propagation and localisation characteristics of oscillations in lattices
of various dimensions were studied and a new method for the localized states
description based on Jmatrix was suggested.
 A number of microscopic calculations on the atomic dynamics of the
definite crystal structures both perfect and defected were made.
 Phonon spectra behaviour of crystals with the weakened effect of crystal
atoms ordering regularity (systems with complex defects, multilayered
structures of HTSCtype, nanoclusters, etc.) was investigated on microscopic
level; it was found that the oscillatory characteristics of such
compositions were definitely conditioned by its strong spatial
nonhomogeneity as well as the local anisotropy of interatomic interaction.
(with E.S. Syrkin and A.M. Kosevich)
 Localization and propagation of vibrations in heterogeneous crystals and
disordered solid solutions
 Creation of calculation models for investigation of electron and phonon
spectra of graphite and carbonic thin films.
Main Publications:
 S.B.Feodosyev, I.A.Gospodarev, E.S.Syrkin, Anomalies of Linear Expansion
Coefficient in Highly Anisotropic Crystals at Low Temperature, Phys, Stat.
Sol (b), 150, K19, 1988.
 S.B. Feodosyev, I.A. Gospodarev, A.M. Kosevich, E.S. Syrkin,
QuasiLowDimensional Effects in Vibrational Characteristics of 3DCrystals,
Phys. Low Dim. Str., 10/11, 209, 1995.
 S.B.Feodosyev, M.A.Mamalui, E.S.Syrkin, Dynamical Characteristics of
Infinite and SemiInfinite 1D Structure with Defects in Presence of
Activation, Synthetic Metals, 121, 1333, 2001.
 I.A. Gospodarev, A.V. Grishaev, E.S. Syrkin, S.B. Feodosyev, Local
Vibrations of FCCCrystals with Two Parametric Substitution Impurities,
Phys. Solid State, 42, N12, 2000.
 S.B. Feodosyev, I.A. Gospodarev, M.A. Strzhemechny, R.J. Hemley, Phonon
Assisted Ortho Para Conversion in Solid H_{2} Under Pressure,
PHYSICA B: Physics of Condensed Matter, 300, 186, 2001.
 A.M. Kosevich, A. Mayer, S.B. Feodosyev, I.A. Gospodarev, V.I. Grishaev,
E.S. Syrkin, Atom Dynamics of MicroClusters on Atomically Smooth Surfaces,
Superlattices and Microstructures, 27, No1, 7, 2000.
 E.T. Verkhovtseva, I.A. Gospodarev, A.V. Grishaev, S.I. Kovalenko, D.D.
Solnyshkin, E.S. Syrkin, S.B. Feodosyev, Atom Dynamics and the Problem of
the Structural Stability of Free Clusters of Solidified Inert Gases, Low
Temperature Physics, 29, No 5, 386, 2003.
 A.V. Kotlyar and S.B. Feodosyev, Local oscillations in crystal lattices
with a simply connected region of the quasicontinuonsphonon spectrum ,
Low Temperature Physics, 32, No 3, 256, 2006.
 I.A. Gospodarev, V.I. Grishaev, O.V. Kotlyar, K.V. Kravchenko, E.V.
Manzhelii, E.S. Syrkin, and S.B. Feodosyev, Ioffe–Regel crossover and boson
peaks in disordered solid solutions and similar peculiarities in
heterogeneous crystal structures Low Temperature
Physics, 34, No 8, 655, 2008.
 E.S. Syrkin, S.B. Feodos’ev, K.V. Kravchenko, A.V. Eremenko, B.Ya.
Kantor and Yu.A. Kosevich, Flexural rigidity of layers and its manifestation
in the vibrational characteristics of strongly anisotropic layered crystals.
Characteristic frequencies and stability conditions in quasitwodimensional
systems, Low Temp. Phys. 35, No 2 158, 2009.
 I.A. Gospodarev, K.V. Kravchenko, E.S. Syrkin and S.B. Feodos’ev
Quasitwodimensional features in the phonon spectrum of graphite Low Temp.
Phys. 35, No 7 589, 2009.
 A. Feher, I.A. Gospodarev, V.I. Grishaev, K.V.
Kravchenko, E.V. Manzheliĭ, E.S. Syrkin and S.B. Feodos’ev, Effect of
defects on the quasiparticle spectra of graphite and graphene, Low Temp.
Phys. 35, No 8,
679, 2009
 I.K. Galetich, I.A. Gospodarev, V.I. Grishaev, A.V. Eremenko, K.V.
Kravchenko, , V.A. Sirenko, S.B. Feodosyev, Vibrational characteristics of
the niobium dichalcogenide. Bulk samples and nanofilms, Superlattices and
Microstructures, 45, No 6, 564, 2009
 I.A. Gospodarev, V.V. Eremenko, K.V. Kravchenko, V.A. Sirenko, E.S.
Syrkin and S.B. Feodos’ev Vibrational characteristics of niobium diselenide
and graphite nanofilms Low Temp. Phys. 36,
No 4,
344 2010.
 Alexander Feher, Eugen Syrkin, Sergey Feodosyev, Igor Gospodarev and
Kirill Kravchenko QuasiParticle Spectra on Substrate and Embedded Graphene
Monolayers, in: “Physics and Application of Graphene – Theory” (ed. S. Mikhailov)
“InTex” Open Access Publisher, ISBN 9789533079967 Croatia, 2010
 A Feher,
E. Syrkin, I. Gospodarev, E. Manzhelii, A. Kotlyar, K. Kravchenko, The
Features of Low Frequency Atomic Vibrations and Propagation of Acoustic
Waves in Heterogeneous Systems, in: “Waves in Fluids and Solids” (ed. R.P. Vila)
“InTex” Open Access Publisher, ISBN 9789533072463 Croatia,
2011.
 I. Gospodarev, O.V. Kotlyar, K.V Kravchenko, E.V. Manzhelii, E.S Syrkin,
A.V.Yeremenko, I.K. Galetich, Low Temperature Peculiarities of
QuasiParticle Spectra of Disordered Solid Solutions, in: “Contemporary
Problems of Mathematics, Mechanics and Computer Sciences” (eds. N.N. Kizilova,
G.N. Zholtkevich) PRB Virovec’,ISBN 9789662579925 Ukraine, 2011
 A.Feher, I.Gospodarev, O.Kotlyar, K.Kravchenko, E.Manzhelii, E.Syrkin,
S.Feodosyev Impurity levels in the electron spectra of graphene,
Superlattices and Microstructures, 53, 55, 2013
 I.A. Gospodarev, A.V. Eremenko, K.V. Kravchenko, A.F. Sirenko, V.A.
Sirenko, E. S. Syrkin, S.B. Feodosyev, and Yu. A. Shabakaeva, Distinctive
Features of Thermal Expansion of Niobium Diselenide, Physics of the Solid
State,.
55 No. 4, 825, 2013
