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, at present a Full Member of the National Academy of Sciences of Ukraine. Since 2007 Viacheslav Aleksandrovich Konstantiniv, a Doctor of Physics and Mathematics, is a heat of the department.

Researchers:
Doctors of science - M.I. Bagatskii, B.Ya. Gorodilov, V.A. Konstantinov, V.G. Manzhelii.
Candidates (Ph.D) - V.G. Gavrilko, A.V. Dolbin, V.B. Esel'son, V.V. Katalnikova, O.A. Korolyuk, A.I. Krivchikov, V.P. Revyakin, 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, CHCl3, CH2Cl2, CHF2Cl, CF2Cl2, C6H6, etc.) and their solutions, fullerites (pure and doped), gas hydrates, monoatomic alcohols.

The properties under study: heat capacity, phase transition heats (dP/dT)v, thermal expansion, compressibility, thermal conductivity, permitivity, conversion, quantum diffusion (configuration relaxation).

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 permitivity.

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).

 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 400 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;
- Australian Nuclear Science and Technology Organization, Australia;
- Laboratoire des Colloïdes, Verres et Nanomatériaux Université  Montpellier II France;
- Physics and Astronomy Department Michigan State University East Lansing, USA;
- University of Pittsburgh, Department of Chemistry Pittsburgh, USA;
- Physics & Astronomy Department, Rice University, Houston, USA;
- Institute for Physics of RAS, Russia;
- Mirzo Ulugbek National University of Uzbekistan.

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)