Measurement of Elastic Constants in [N(CH₃)₄]₂ZnI₄ Single Crystal

抄録

Temperature dependences of diagonal elements of the elastic stiffness constant in [N(CH₃)₄]₂ZnI₄ single crystal have been measured between room temperature and about 200K by means of the ultrasonic pulse echo overlap method. In the room temperature phase (phase I), softening of the elastic constant c₅₅ has been observed. The transition temperature has been determined to be T_C1=256K. The second elastic anomaly of phase transition has been observed at T_C2=213K.