Structure of the Laser Host Material LiYF4

Lithium yttrium tetrafluoride, LiYF 4 , M r =171.8, tetragonal, I4 4 /a, a=5.164 (1), c=10.741 (2) A, V=286.5 (1) A 3 , Z=4, D x = 3.99 g cm -3 , λ(Mo Kα)=0.7107 A, μ=204 cm -1 , F(000)=312, T=295 K, R=0.015 for 156 unique observed [F>4σ(F)] reflections. The scheelite (CaWO 4 ) structure is confirmed. Lithium is located at a 4 site with four equidistant fluoride ions. Yttrium is in an eightfold coordination typical for rare-earth ions