Temperature dependent infrared absorption, crystal-field and intensity analysis of Ce3+ doped LiYF4

• 10 K infrared absorption spectrum of LiYF4:Ce3+.
• Comprehensive crystal-field analysis with intensity analysis for the intra-4f transitions.
• Temperature dependent line broadening studies which reveal coupling to low frequency phonon modes.

Infrared absorption has been used to determine the crystal-field levels of the 2F7/2 excited multiplet of trivalent cerium doped into scheelite structure LiYF4 single crystals. A crystal-field analysis well accounts for a total of six experimentally observed energy levels and the ground state g-values as previously determined by electron paramagnetic resonance, whilst intensity simulations confirm the experimentally assigned level symmetries. Temperature dependent spectral line broadening measurements highlight the importance of coupling to low frequency phonon modes of the YF8 tetrahedron.