Pressure Effect on Structural and Phonon Properties of Mixed Alloys Compounds

Abstract:

We report pressure induced structural phase transition, elastic and thermal properties of concentrations of U_XLa_1-XS (x= 0.80, 0.60 and 0.50) compound, using modified inter-ionic potential theory (MIPT), which parametrically includes the effect of coulomb screening. The calculated equation of state, phase transition pressure, bulk modulus and volume collapse are agree well with the available theoretical or experimental findings. We have also reported the second order elastic constants and Debye temperature of this compound for first time. We have also reported the Phonon properties of U_xLa_1-xS (x = 0.80, 0.60, 0.50) compounds by using breathing shell model (BSM). The present model includes breathing motion of electron shells of rare earth atom due to f-d hybridization. The calculated phonon dispersion curves of U_xLa_1-xS are presented follow the same trend as observed in uranium chalcogenides. We have reported doping effect of La on phonon frequencies at X and L-points for the first time. The LO-TO splitting increases as decreasing concentration of La.Keywords: Phase Transition, Elastic Properties, Debye Temperature, Phonon Dispersion

• Periodical: Advanced Materials Research (Volume 1047)
• Pages: 85-93
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1047.85
• Online since: October 2014
• Authors: Ashok K. Ahirwar*, Mahindra Aynyas, S.P. Sanyal
• Keywords: Debye Temperature, Elastic Properties, Phase Transition, Phonon Dispersion

References

[1] U Benedict Journal of Less- Common Metals 128 (1987) 7.

[2] T Le Bihan, A Bombardi, M Idiri, S Heathman and A Lindbaum Journal of Phys. Condens. Matter 14 (2002) 10595.

DOI: 10.1088/0953-8984/14/44/339

[3] P K Jha, S P Sanyal Solid State Commun. 105 (1998) 455.

[4] P K Jha, S P Sanyal Pramana J. Phys. 43 (1994) 193.

[5] S Dabos, C Dufour, U Benedict, J C Spirlet, M Pages Physica B 144 (1986) 79.

[6] P K Jha, S P Sanyal Physica B 20 (1995) 108.

[7] P K Jha, S P Sanyal Phys. Stat. Sol. (b) 13 (1997) 200.

[8] W G Stirling, G H Lander, O Vogt J. Phys. C 16 (1983) 4093.

[9] J Neuenschwander, O Vogt, E Voit, P Wachter Physica B 144 (1986) 66.

[10] T M Holden, W J L Buyers, E C Svensson, J A Jackman, A F Murray, O Vogt, J. Appl. Phys. 53 (1982) (1967).

[11] A L Cornelius, J S Schilling, O Vogt, K Mattenberger, U Benedict J. Magn. Matter 161 (1996) 169.

[12] O Vogt K Mattenberger J. Alloy. Compound 223 (1995) 226.

[13] P de, V du Plessis, D L Tillwick, J. Appl. Phys. 50 (1979) 1834.

[14] J S Olsen, S Stenstrup, L Gerward, U Benedict, J C Spirlet , G D Rectt, J. Less- Common. Met. 98 (1984)291.

[15] G Vaitheeswaran, V Kanchana, M Rajagopalan, J Phys. Chem. Solids 64 (2003) 15.

[16] G Vaitheeswaran, V Kanchana, S Heathman, M Idiri T Le Bihan, S Svane, A Delin, B Johansson, Physical Rev. B 75 (2007) 184108.

DOI: 10.1103/physrevb.75.184108

[17] P K Jha, S P Sanyal, Physica C 262 (1996) 259-262.

[18] P K Jha, S P Sanyal, Physica C 271 (1996) 6-10.

[19] M Born, K Hung, Dynamical Theory of Crystal Lattices, Oxford Univ. (1954).

[20] J A Jackman, T M Holden, W J L Buyers, Pde. V Duplesis. Phys Rev B 33, (1986) 7144 -7153.

[21] P K Jha, S P Sanyal, Physica B, 216, (1995) 125-131; Ind. J. of Pure and Appl. Phys. 31(1993)469-473.

[22] B S Arya, M Aynyas, S P Sanyal, J. Nuc. Mats. 393, (2009) 381-386.

[23] A Singh, M. Aynyas, S P Sanyal Phase Transition 82: 8 (2009) 576.

[24] A Rukmangad, M Aynyas, S P Sanyal, Ind. Journal of Pure & Appl. Phys. 47 (2009) 114.

[25] V Mankad, N Rathod, S D Gupta, S K Gupta and P K Jha, Mat. Chem. and Phys. 129 (2011)816-822.