Abstract
The Raman spectra of virtual ferroelastic Hg2I2 crystals have been studied in a broad range of hydrostatic pressures. Linear pressure dependences of phonon frequencies are obtained at P < P c, which exhibit jumps and breaks at the phase transition point (P c = 9 kbar). Grüneisen parameters of the Hg2I2 crystals are determined. The spectra of a ferroelastic phase (P > P c) in various polarizations exhibit the excitation of new lines from the X point of the Brillouin zone, including transverse (TA) and longitudinal (LA) acoustic phonons. Based on analysis of the experimental and theoretical results, the Raman spectra of ferroelastic Hg2I2 crystals are interpreted and a model of the phase transition in these crystals is proposed.
Similar content being viewed by others
References
M. Kars, T. Roisnel, V. Dorcet, A. Rebbah, and O.-D. L. Carlos, Acta Cryst. E 68, i11 (2012).
H. Mark and J. Steinbach, Z. Kristallogr. 64, 78 (1926).
Proceedings of the 2nd Int. Symp. on Univalent Mercury Halides, Trutnov, ChSFR (1989).
Č. Barta, A. A. Kaplyanskii, V. V. Kulakov, B. Z. Malkin, and Yu. F. Markov, Sov. Phys. JETP 70, 744 (1976).
B. S. Zadokhin, A. A. Kaplyanskii, Yu. F. Markov, and Č. Barta, Sov. Phys. Solid State 20(10), 1800 (1978).
E. M. Roginskii, A. A. Kvasov, Yu. F. Markov, and M. B. Smirnov, Tech. Phys. Lett. 39(5), 413 (2013).
Č. Barta, A. A. Kaplyanskii, Yu. F. Markov, and V. Yu. Mirovitskii, Sov. Phys. Solid State 27(8), 1497 (1985).
N. N. Stepanov, Yu. F. Markov, and V. Yu. Mirovitskii, Prib. Tekh. Eksp., No. 5, 214 (1986).
I. M. Silvestrova, Ju. V. Pisarevskii, N. A. Moiseeva, and L. M. Beljaev, Krist. Tech. 12, 987 (1977).
S. Grimme, J. Comput. Chem. 27(15), 1787 (2006).
Author information
Authors and Affiliations
Corresponding author
Additional information
Original Russian Text © Yu.F. Markov, V.Yu. Mirovitskii, E.M. Roginskii, 2014, published in Pis’ma v Zhurnal Tekhnicheskoi Fiziki, 2014, Vol. 40, No. 22, pp. 12–20.
Rights and permissions
About this article
Cite this article
Markov, Y.F., Mirovitskii, V.Y. & Roginskii, E.M. Pressure behavior of phonons and phase transition effects in Hg2I2 model virtual ferroelastics. Tech. Phys. Lett. 40, 992–995 (2014). https://doi.org/10.1134/S1063785014110248
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S1063785014110248