Ionic conductivity of yttrium fluoride and lutetium fluoride.
At the transitions from the low-temperature orthorhombic forms of lutetium fluoride and yttrium fluoride to the high-temperature hexagonal forms, there are increases of several orders of magnitude in the ionic conductivities. In the high-temperature phases the conductivities are comparable to those of typical ionic melts. These fluoride compounds are therefore solid electrolytes.
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