1Pohl Institute of Solid State Physics, Tongji University, Shanghai 200092
2Institute fúr Experimentalphysik III, AG Festkórperspektroskopie, Ruhr-Universität Bochum, 44780 Bochum, F. R. G., P. O. Box 102148
3International Center for Materials Physics, Academia Sinica, Shenyang 110015
Ammonium Ion Motion and Phase Transitions in (ND4)2TeCl6 Studied by Raman Scattering
SHI Jin-rong1;MÜLLER S2;ARNSCHEIDT B2;PELZL J2;XU Yong-chen1;WU Xian2,3
1Pohl Institute of Solid State Physics, Tongji University, Shanghai 200092
2Institute fúr Experimentalphysik III, AG Festkórperspektroskopie, Ruhr-Universität Bochum, 44780 Bochum, F. R. G., P. O. Box 102148
3International Center for Materials Physics, Academia Sinica, Shenyang 110015
Abstract： The internal vibrations of the ammonium ion in (ND4)2TeCl6 have been studied by Raman scattering in the temperature range 4.2-300K. Splittings of A1-, E-, and T2-modes have been observed at Tc2 = 48 K and Tc3 = 28 K. These splittings were well interpreted by group theoretical correlation method. The reason for the transitions at Tc2 and Tc3 may be the decrease of the force constant in the deuterated ammoniumion.
1996, Vol. 13 
