Institute for Low Temperature Physics and Engineering

Department for Low Temperature Structure Studies of Solids

Department Head: DrSci, Associate Member of NASU, Professor Mikhail STRZHEMECHNY

tel: +(380)-57-340-91-83


The Department was organized in 1990 by amalgamating the former Laboratory of Structure-Sensitive Properties of Solids and the Single-crystal x-ray Group from the Biophysics Department. The old Laboratory was headed by L. M. Polyakov (from 1962 till 1964), D. N. Bolshutkin (from 1965 till 1970), I. N. Krupskii (from 1970 till 1986), M. A. Strzhemechny (from 1986 till 1988), and A. I. Erenburg (from 1988 till 1990).

In 2006 the Department incorporated the Laboratory Optics of Molecular Crystals, which was headed by Prof. A.A. Avdeenko, which initiated a complex structure-optical studies of novel materials, including the fullerites, both pure and doped with gases, molecular (organic) crystals, etc.

At the beginning (from 1962 to 1966) the main objects of investigation were plastic and strength properties of cryocrystals, i.e., solids with low melting temperatures as well other solids that required in situ sample growing. By and by the main interests of the Department have shifted to other problems of solid state physics, namely, the structure and dynamics of the above listed solids. In addition, by the beginning of the 90-ies the Department was involved in studies of the structure and thermodynamics of pure and doped fullerite C60. In the early 2000-ies investigations into the structure and luminescence properties of bromo-substituted benzophenones have been initiated.

At present (June 2015) Department staff includes 13 researchers and 2 PhD students, among them two Doctors of Science (M. A. Strzhemechny and A.I. Prokhvatilov) as well as nine PhD researchers: L.M. Buravtseva, V.V. Danchuk, P.V. Zinoviev, V.N. Zoryanskii, N.V. Krainyukova, I.V. Legchenkova, O.S. Pyshkin, A.A. Solodovnik, and Yu.E. Stetsenko.

Main scientific fields:
- structure of solids over a wide temperature range from liquid helium to room temperature, using x-ray and electron diffraction;
- lattice dynamics of molecular crystals with account of internal degrees of freedom;
- luminescence of molecular solids;
- phase transitions in solids;
- plasticity of cryocrystals.

Materials for investigation:
- cryocrytals, i.e. materials with low melting points, such as rare gas solids, hydrogen, nitrogen, carbon oxide and monoxide, nitrous oxide, methane, as well as binary alloys thereof;
- fullerenes and carbon nanotubes;
- molecular (organic) solids such various phenone derivatives, etc.;
- magnetically ordered materials,

The most important results obtained in this Department:
- the extensive structure studies of the various molecular cryocrystals and the orientational order therein, summarized in  four books:
Cryocrystals (eds. B. I. Verkin and A. F. Prikhot'ko) Naukova Dumka, Kiev (1983) [in Russian].
Physics of Cryocrystals (eds. Yu. A. Freiman, V. G. Manzhelii, M. L. Klein, and A. A. Maradudin) AIP Publishers, New York (1996).
V.G.Manzhelii, A.I.Prokhvatilov, I.Ya. Minchina, and L.D. Yantsevich. Handbook of Binary Solutions, Begell House Inc., New York - Wallinford (1996).
V.G.Manzhelii,A.I.Prokhvatilov, V.G.Gavrilko, A.P.Isakina. Handbook of Structure and Thermodynamic Properties of Cryocrystals. Begell House Inc., New York - Wallinford (1997).
- determination of the structure of many molecular solids such as caffeine, adenine, theofiline, and other.
- the first results on the plasticity characteristics of many cryocrystals, including the quantum crystal of hydrogen and solid nitrogen
- x-ray and electron diffraction determination of the structure of various cryoalloy systems such as solid mixtures of simplest molecular components (nitrogen, carbon dioxide and monoxide, methanes, etc.) and rare gases with an eye for studying the molecular glass aspects.
- combined structure-luminescence studies of fullerite C60 saturated with gases, which allowed not only the observation of the strong dependence of the orientational glassification point Tg on saturation but also explanation of the effect of the sharp decrease of lamination intensities upon crossing Tg;
- explanation of the huge (by a factor of 106) acceleration of the conversion in solid hydrogen at very high pressures;
- observation and explanation of the cardinal changes of the luminescence of ortho-bromobenzophenone crystal and glass with temperature;
- growth of two polymorphs of para-bromobenzophenones and the comparative study concerning the triplet exciton dynamics in the two polymorphs.

The Department has experimental setups and the respective measurement procedures, originally developed and successfully run for years, among which are:
- liquid-helium powder x-ray cryostat operating from 2 K to room temperature;
- liquid-helium cryostat for electron diffraction studies from 2 K to room temperature;
- setup for studies of spectral luminescence properties of emitters with low quantum output, working over a wide temperature range (10 to 300 K);
- setup for measuring integrated and microsecond time-resolved luminescence spectra as well as relative quantum gain of molecular crystals in the temperature range from 1.6 to 300K.