The effective interatomic potential in Ni,,Dy,, glass is obtained with the experimental structure factor S(Q). This potential is compared with those computed using Percus-Yevick (PY) and hypernetted chain (HNC) approximations. A theory of phonons in amorphous solids is employed to compute the eigenfrequencies of the longitudinal and transverse phonon modes with these diffcrcnt potentials and the results are compared with each other. The elastic and thermodynamic properties of this glass are also studied using the longitudinal and transverse sound velocities estimated from the slope of the long-wavelength limit of the dispersion relations.') Jaipur 302004, India.

Analytical expressions for the dispersion of the longitudinal and transverse phonons are obtained for a two-component metallic glass employing a self-consistent phonon theory for amorphous solids as developed by Takeno et al. The effective pair potential used for the computation of the eigenfrequencies of the longitudinal and transverse phonons in Ca70Mg30 glass is obtained by making use of the Ashcroft pseudopotential for the pure components. Eigenfrequency expressions reproduce the main characteristic features of the dispersion curves obtained by neutron scattering and computer simulation techniques, both for the longitudinal and the transverse phonons. The results of the present computations are in good agreement with the available experimental data.

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Kinematical studies of crystallization in bulk amorphous Se70Te30‐xCdx (x = 2, 6, 8, and 10) glasses were made using differential scanning calorimetry. The crystallization data are examined in terms of modified Kissinger and Matusita equations for the nonisothermal crystallization, and the activation energy for crystallization Ec is evaluated from the data obtained at different heating rates. The results show bulk nucleation with two‐dimensional growth for these glasses. The enthalpy release during crystallization for all the compositions is measured. Maximum enthalpy release is obtained for the Se70Te28Cd10 glass having the highest thermal stability and the enthalpy release for Se70Te20Cd10, having the lowest thermal stability as indicated by the Tc ‐ Tg values, is found to be minimum.