Low Temperature Physics: 29, 720 (2003); https://doi.org/10.1063/1.1614176 (5 pages)
Физика Низких Температур: Том 29, Выпуск 9-10 (Сентябрь 2003), c. 961-966    ( к оглавлению , назад )

Translational-rotational interaction in dynamics and thermodynamics of 2D atomic crystal with molecular impurity

T.N. Antsygina, M.I. Poltavskaya, and K.A. Chishko

B. Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine, 47 Lenin Ave., Kharkov 61103, Ukraine
E-mail: chishko@ilt.kharkov.ua


The interaction between the rotational degrees of freedom of a diatomic molecular impurity and the phonon excitations of a two-dimensional atomic matrix commensurate with a substrate is investigated theoretically. It is shown, that the translational-rotational interaction changes the form of the rotational kinetic energy operator as compared to the corresponding expression for a free rotator, and also renormalizes the parameters of the crystal field without change in its initial form. The contribution of the impurity rotational degrees of freedom to the low-temperature heat capacity for a dilute solution of diatomic molecules in an atomic two-dimensional matrix is calculated. The possibility of experimental observation of the effects obtained is discussed.

68.35.Dv - Composition, segregation; defects and impurities
68.35.Ja - Surface and interface dynamics and vibrations
68.65.+g -