Oxide solubility and Raman spectra of NdF_3-LiF-KF-MgF_2-Nd_2O_3 melts

摘要

The solubility of Nd_2O_3 in NdF_3-LiF-MgF_2 metals is about 0.08-0.38 mol% when the NdF_3 concentration varies from 15 to 30 mol% at 900 deg C. The solubility increases from 0.13 mol% at 750 deg C to 0.22 mol% at 900 deg C in the NdF_3-LiF eutectic. When MgF_2 is added to NdF_3-LiF binary metals saturated with Nd_2O_3, the Nd_2O_3 solubility seems to decrease slightly at 30 mol% NdF_3, while a slight increase was observed with 15 mol% NdF_3 in the binary. When dissolving Nd_2O_3 in the NdF_3-LiF eutectic Raman spectroscopy showed that the complex ions NdOF_x~(x-1)- and Nd_2OF_(x+3)~(x-1)- may form in the melt. The most reasonable candidates seem to be: NdOF_4~93-) and NdOF_5~94-) among the mononuclear compounds and Nd_2OF_210~(6-), Nd_2OF_8~(4-) among the binuclear complexes.