A K Sood et al 1981 J. Phys. C: Solid State Phys. 14 5215 doi:10.1088/0022-3719/14/33/026
A K Sood, A K Arora, S Dattagupta and G Venkataraman
Show affiliationsThe Ag internal mode of the sulphate ion in potash alum is studied by Raman scattering as a function of temperature. This mode shows a splitting on account of the fact that a small fraction of S-O bonds point towards K+ while a larger fraction point towards Al3+. The area under each peak is a measure of the number of sulphate units having the corresponding orientation. Above 200K, the observed area ratio follows the expected exponential dependence on the temperature, and may be understood on the basis of phonon-assisted reorientations of the sulphate ion between the two configurations. At lower temperatures, there is a marked deviation from the exponential form. This is explained by invoking a temperature-independent contribution to the orientation rate. A detailed lineshape analysis is made and compared with experiment. The possible origin of the temperature-independent relaxation mechanism is also discussed.
Issue 33 (30 November 1981)
A K Sood et al 1981 J. Phys. C: Solid State Phys. 14 5215
Xiang-Yu Ge et al 2002 J. Phys. A: Math. Gen. 35 6197
D A Telnov and S -I Chu 1995 J. Phys. B: At. Mol. Opt. Phys. 28 2407
Michael Martin Nieto and Slava G Turyshev 2004 Class. Quantum Grav. 21 4005
I Henderson et al 1993 Phys. Med. Biol. 38 1611
R Egydio de Carvalho et al 2006 J. Phys. A: Math. Gen. 39 3561
W Vogelsang and M R Whalley 1997 J. Phys. G: Nucl. Part. Phys. 23 A1
J.D. Sethian et al 2003 Nucl. Fusion 43 1693
Laura Silva et al. 1998 ApJ 509 103
Martin Sieber 2000 J. Phys. A: Math. Gen. 33 6263