Single-crystal elastic constants of MgZn2 in the temperature range from 4.2 to 300 K

The single-crystal elastic constants of MgZn2 were determined by McSkimin's pulse super-position method. In the temperature range between 150 and 300 K the elastic moduli of C11, C33, and C44 increase linearly with decreasing temperature. This linear range is followed by a transition range within which the slope of the curve has lower values. For T < 20 K the elastic moduli are constant. The temperature dependence of the elastic constants C12 and C13 shows an anomalous behaviour. The decrease of C12 and C13 below 90 and 120 K, respectively, indicates a martensitic transformation of MgZn2. The Debye temperature is 325 K.