Experimental and Theoretical Studies of SASeD Doped with Cr³⁺

Abstract

The results of optic and EPR measurements are presented. The transmition bands observed during optic measurements (above and below T_c) have been identified. It is shown that the phase transition, taking place at 180 K reflects itself only in a small parallel shift of the whole spectrum towards higher frequencies. Temperature dependence of the EPR spectrum reveals not only the transition at 176 K but two other anomalies detected at T₁ = 156 K and T₂ = 285 K. An outline of the theory predicting the existence of these anomalies is discussed in terms of the so-called cluster model.

Keywords:

• Sodium ammonium sulphate dihydrate
• phase transitions
• EPR
• cluster model