STRUCTURE OF MOLTEN YTTRIUM CHLORIDE IN AN IONIC MODEL

We report calculations of the liquid pair structure of YCl3 as a prototype for strongly ionic melts of lanthanide metal trichlorides. The calculations adopt an ionic model involving a pair potential of the Busing type, with parameters for the Y3+ ion adjusted to the Y-Cl bond length in the YCl3 crystal and to the breathing mode frequency of the (YCl6)3- octahedral unit. The model is solved in the hypernetted chain approximation and the results are tested against neutron diffraction data on the Faber-Ziman structure factor and the total pair correlation function of molten YCl3. The calculated partial structure factors and pair correlation functions provide insight into the origin and nature of the short-range and intermediate-range order in the melt.