Single crystal elastic constants of neodymium from 4.2 to 300K

Four of the five independent single crystal elastic constants of Nd have been measured, using standard pulse echo ultrasonic techniques over the temperature range 4.2-300K. All four constants, c 11 , c 33 , and c 66 = 1 / 2 (c 11 -c 12 ) show evidence of the magnetic phase changes at approximately 20K and approximately 7.5K. The behaviour of c 11 and c 66 in particular casts some light on the recent neutron diffraction studies of Nd.