Reorientation of Na⁺-anion vacancy and Y³⁺-fluorine interstitial complexes in CdF₂

The ionic thermocurrents (ITC) of undoped, NaF- and YF 3 -doped CdF 2 were measured between 90 and 320 K on samples polarized at room temperature and below. It is shown that the two peaks observed below 200 K are due to two states of Na + -anion vacancy and Y 3+ -fluorine interstitial complexes with different binding energies and activation energies of reorientation of about 0.22 and 0.34, and 0.21 and 0.36 eV respectively. It is further shown that these ITC peaks are enhanced due to a space- charge formation.