Shchur Ya.I., Trach I.B., Vlokh O.G.
Lattice dynamics study of Cs2CdBr4 crystal comprising both the Raman-scattering experiment and numerical simulation has been performed in the high-temperature orthorhombic phase (Pnma). The observation of extra Raman lines, forbidden by factor-group analysis reveals an existence of orientational disorder of the CdBr42- groups. An interpretation of Raman spectra was made in the framework of a semi-empirical model taking into consideration the long-range Coulumbic, short-range and covalent interactions. The agreement between the theoretical and experimental phonon frequencies is reasonable.
Keywords: lattice dynamics, phonon, Raman spectra
doi 10.3116/16091833/2/4/192/2001
1. Altermantt D, Arend H, Niggli A and Petter W, 1979. Mater. Res. Bull.
14: 139.
2. Plesko S, Kind R and Arend H, 1980. Ferroelectrics 26: 703.
3. Plesko S, Kind R and Arend H, 1980. Phys. Status Solidi (a) 61:
87.
4. Maeda M, Honda A and Yamada N, 1983. J. Phys. Soc. Japan 52: 3219.
doi:10.1143/JPSJ.52.3219
http://dx.doi.org/10.1143/JPSJ.52.3219
5. Altermatt D, Arend H, Gramlich V, Niggli A and Petter W, 1984. Acta
Cryst. B40: 347.
6. Zaretskii V and Depmeier W, 1991. Abstract from 7th European Meeting
on Ferroelectricity (Dijon: Univercity of Burgundy): 207.
7. Kityk AV, Mokry OM, Soprunyuk VP and Vlokh OG, 1993. J.Phys.:Condens.
Matter 5: 5189.
doi:10.1088/0953-8984/5/29/014
http://dx.doi.org/10.1088/0953-8984/5/29/014
8. Kuzel P, Moch P, Gomez-Cuevas A and Dvorak V, 1994. Phys. Rev. B
49: 6553.
doi:10.1103/PhysRevB.49.6553
http://dx.doi.org/10.1103/PhysRevB.49.6553
9. Kuzel P, Dvorak V and Moch P, 1994. Phys. Rev. B 49: 6563.
doi:10.1103/PhysRevB.49.6563
http://dx.doi.org/10.1103/PhysRevB.49.6563
10. Rodriguez V, Couzi M, Gomez-Cuevas A and Chaminade JP, 1991. Phase
Transitions 31: 75.
11. Torgashev I, Yuzyuk YuI, Burmistrova LA, Smutny F and Vanek P,
1993. J. Phys.: Condens. Matter 5: 5761.
doi:10.1088/0953-8984/5/32/007
http://dx.doi.org/10.1088/0953-8984/5/32/007
12. Shchur Ya, Kamba S and Petzelt J, 1999. J.Phys.:Condens. Matter
11: 3601.
doi:10.1088/0953-8984/11/17/318
http://dx.doi.org/10.1088/0953-8984/11/17/318
13. Shchur Ya, Kamba S and Petzelt J, 1999. J.Phys.:Condens. Matter
11: 3615.
doi:10.1088/0953-8984/11/17/319
http://dx.doi.org/10.1088/0953-8984/11/17/319
14. Vanek P, Studuicka V and Havrankova M, 1996. Mater.Res.Bull. 31:
113.
doi:10.1016/0025-5408(95)00174-3
http://dx.doi.org/10.1016/0025-5408(95)00174-3
15. Nakamoto K, 1978. Infrared and Raman Spectra of Inorganic and Coordination
Compounds, John Wiley * Sons, New York.
16. Altermantt D, Arend H, Gramlich V, Niggli A and Petter W, 1984.
Acta Crystallogr. B 40: 347.
doi:10.1107/S0108768184002275
http://dx.doi.org/10.1107/S0108768184002275
17. Itoh K, Hinasada A, Matsunaga H and Nakamura E, 1983. J.Phy.Soc.Jpn.
52: 664.
doi:10.1143/JPSJ.52.664
http://dx.doi.org/10.1143/JPSJ.52.664
18. Massa NE, Ullman FG and Hardy JR, 1983. Phys.Rev.B 27: 1523.
doi:10.1103/PhysRevB.27.1523
http://dx.doi.org/10.1103/PhysRevB.27.1523
19. Noiret I, Guinet Y and Hedoux A, 1995. Phys.Rev.B 52: 13206.
doi:10.1103/PhysRevB.52.13206
http://dx.doi.org/10.1103/PhysRevB.52.13206
20. Chaplot SL, Rao KR and Roy AP, 1984. Phys. Rev. B 29: 4747.
doi:10.1103/PhysRevB.29.4747
http://dx.doi.org/10.1103/PhysRevB.29.4747
21. Kitaigorodskii AI and Mirskaya KV, 1964. Kristallografiya 9: 174.
22. Chaplot SL, 1978. Rep. BARC-N972 Bhabha Atomic Research Center
Bombay.
23. de Pater CJ, 1079. Acta Crystallogr. B 35: 299.