Change of compressibility at the glass transition and Prigogine-Defay ratio in ZrTiCuNiBe alloys

The change of the compressibility at the glass transition T-g is evaluated from pressure experiments in the liquid and the glassy state of the ZrTiCuN iBe bulk metallic glass forming system. Via the enthalpy recovery method, w e derive an increase of T-g with pressure of 3.6 K/GPa. Comparing the chang es of the compressibility, the specific heat capacity, and the thermal expa nsion coefficient at T-g, we estimate for the first time a Prigogine-Defay ratio in metallic systems. This ratio is about 2.4 for the present alloy an d compares well with known nonmetallic glass forming systems. [S0031-9007(9 8)08212-X].