Neutron small-angle scattering on molten Ga-Tl alloys

Molten alloys of the system Ga-Tl have been investigated in dependence on t emperature near the miscibility gap using small-angle neutron scattering. F or the alloy of critical composition (40 at.% Tl) an increasing scattering intensity at low momentum transfer is observed, if the temperature is reduc ed to the critical temperature, T-C. At T similar to T-C the increase reach es its maximum and decreases if the temperature is decreased. The data can be described by the Ornstein-Zernike formalism and a temperature-dependent correlation length is derived. For the other alloys, no temperature-depende nt effects are observed in the covered range of momentum transfer. (C) 1999 Elsevier Science B.V. All rights reserved.