Cs2LiLuCl6: Zwei Formen mit zwei Umwandlungen im festen Zustand

Cs₂LiLuCl₆: Two Modifications with Two Transitions in the Solid State At ambient temperature Cs₂LiLuCl₆ crystallizes with the trigonal HT-K₂LiAlF₆ structure type (?6L-type”? form I, L). With increasing temperature a reversible, reconstructive solid to solid first order phase transition to the cubic-face centered K₂NaAlF₆-type (?elpasolite”?, form II) occurs at ≈? 325°C with a negative volume discontinuity. Above ≈? 510°C up to the melting point (≈? 675°C) again the 6L-type is observed (form I, H). The likewise reversible phase transition proceeds with a positive volume discontinuity. In both phase transitions 60° rotations occur within densest packed layers with 0 0.1] as rotation axis.