Volume magnetostriction of valence fluctuating compounds EuNi2 (Si1-xGex)(2)

In order to investigate a field-induced valence transition of Eu compounds, volume magnetostriction has been measured in high magnetic fields for EuNi 2(Si1-xGex)(2). A large volume magnetostriction of similar to 1.2% is obser ved for x = 0.82. The magnetovolume coupling constant of the valence fluctu ating compounds of x less than or equal to 0.82 is found to be about 30 tim es larger than that of divalent compounds of x greater than or equal to 0.8 5. (C) 2000 Elsevier Science B.V. All rights reserved.