B.I. Verkin Institute for Low Temperature Physics and Engineering


DEPARTMENT OF THERMAL PROPERTIES OF MOLECULAR CRYSTALS.

Head of Department: Doctor of Physics & Mathematics Viacheslav Aleksandrovich KONSTANTINOV


The department (laboratory) was established in 1962. Since 1962 up to 2007 it was headed by Vadim Grigorievich Manzhelii (1933-2013) , a Full Member of the National Academy of Sciences of Ukraine (1990). Since 2007 Viacheslav Aleksandrovich Konstantinov, a Doctor of Physics and Mathematics, is a heat of the department.

Researchers:
Doctors of science - M.I. Bagatskii, .AV. Dolbin, V.A. Konstantinov, A.I. Krivchikov
Candidates (Ph.D) - V.G. Gavrilko, V.G. Vinnikov, V.B. Esel'son, O.A. Korolyuk, V.P. Revyakin, O.O. Romantsova, V.V. Sagan, V.V. Sumarokov

First row (left to right): B.Ya. Gorodilov, M.I. Bagatskii, V.G. Manzhelii, V.A. Konstantinov, A.V. Dolbin.
Second row (left to right): V.P. Revyakin, V.B. Esel'son, O.A. Korolyuk, A.I. Krivchikov, V.V. Katalnikova, V.V. Sumarokov, V.G. Gavrilko.

The main research trends: equilibrium and kinetic properties of quantum molecular crystals (H2, HD, D2, CH4) and their solutions, classical cryocrystals (Ne, Ar, Kr, Xe, N2, CO2, CO, N2O, NH3, CH4, CD4, CCl4, SF6, etc.) and their solutions, freons of the methane and ethane series, simple hydrocarbons, alcohols, gas hydrates, fullerites, nanotubes and other nanomaterials (pure and doped).

The properties under study: heat capacity, phase transition heats _, thermal expansion, compressibility, thermal conductivity, dielectric permittivity, conversion, quantum diffusion (configuration relaxation), thermo-stimulated desorption.

The studies cover the intervals of temperatures 0.4 - 300K and pressures up to 8000 atm.

Experimental and methodical potentialities:

Low temperature dilatometry to investigate thermal expansion of solids in the interval 1 - 24K, low temperature adiabatic calorimetry to investigate heat capacity and thermal effects (0.4 - 300K), experimental methods to investigate isobaric and isochoric thermal conductivities (2 - 300K), methods of investigation of thermo-stimulated desorption.

Basic results. The following effects have been detected and investigated at the Department:

- quantum diffusion in solid deuterium;
- considerably decreased transfer of helium by a super-fluid film at the solid parahydrogen surface;
- glass-like behavior of weak cryocrystal solution;
- new mechanisms of strong impurity impacts on thermal properties of crystals at low temperatures;
- negative thermal expansion of fullerite C60 at helium themperatures;
- nuclear spin conversion of deuteromethane in solid CD4-Kr solution at helium temperatures;
- existence of various orientational glasses and their mutual transformation in fullerite C60 doped with gases;
- glass-like behavior of thermal conductivity of clatrate hydrates in a wide range of temperatures (2-200 K);
- quantum diffusion of impurities He, H2, Ne in C60 at low temperatures (T <80 K);
- the coefficient of radial thermal expansion of the nanotubes was first measured and the processes of the spatial distribution of impurity particles on the surface and inside of the nanotube bundles were studied;
- the heat capacity of one-dimensional (1D) chains of atoms obtained by gas adsorption in the grooves bundles of carbon nanotubes was first experimentally investigated.

 It was been shown experimentally that the quantum diffusion in solid hydragen and deuterium is determined by tunnel transfer of the angular momentum of the molecule rather than by mass transfer. Partial dipolar ordering has been revealed in solid CO and N2O at helium temperatures. The effect of an increase in the isochoric thermal conductivity with temperature has been defected and interpreted for some molecular crystals in the region above the Debye temperature. The isotopic effect in the thermal conductivity of solid concentrated orientationally-disordered solutions of CD4 and CH4 in Kr has been investigated and explained. It has been shown experimentally that a hibrid mechanism of CD4 and CH4 molecule conversion predominates in CD4-Kr and CH4-Kr solutions at helium temperatures.

The researchers of the Department have about 450 publications in scientific journals.

 The researchers of the Department maintain a continuous exchange of scientific information and conduct joint studies in cooperation with scientists in different countries. In particular, the scientific contacts are action with the following research centers:

- Department of Experimental Physics, Umea University, Sweden;
- W. Trzebiatowski Institute of Low Temperature and Structure Research PAS, Poland,
- Laboratoire des Colloides, Verres et Nanomateriaux Universite Montpellier II France;
- Physics and Astronomy Department Michigan State University East Lansing, USA;
- Instituto de Estructura de la Materia, CSIC, Spain;
- Institut fur Experimentelle and Angewandte Physik, Germany;
- Institute for Physics of RAS, Russia;
- Institute of Thermal Physics, Ural Branch of the Russian Academy of Sciences, Russia;
- Kazakh National University, Almaty, Kazakhstan;
- Faculty of Science Osaka City University, Japan.

The researchers of the Department are co-author of seven monographs:

1. “Properties of solid and liquid hydrogen (Izdatel’stvo Standartov, Moscow, 1969) [in Russian] (English edition - Jerusalem, Israel,1971)

2. “Cryocrystals” (Naukova Dumka, Kiev, 1983) [in Russian]

3. “Properties of condensed phases of hydrogen and oxygen” (Naukova Dumka, Kiev, 1984) [in Russian ]

4. "Handbook of Properties of Condensed Phases of Hydrogen and Oxygen" (Hemisphere Publishing Corporation, 1991)

5. "The Physics of Cryocrystals" (AIP Press, New York, 1996)

6. "Binary Solutions of Cryocrystals" (Begell House Inc., 1997)

7. "Structure and thermodynamic properties of cryocrystals (handbook)" (Begell House Inc., 1999)