Evidence for Multiple Phase Transitions in La1-xCaxCoO3
Abstract
We report thermal-expansion and specific-heat data of the series La1-xCaxCoO3 for 0 <= x <= 0.3. For x = 0 the thermal-expansion coefficient alpha(T) features a pronounced maximum around T = 50 K caused by a temperature-dependent spin-state transition from a low-spin state (S=0) at low temperatures towards a higher spin state of the Co3+ ions. The partial substitution of the La3+ ions by divalent Ca2+ ions causes drastic changes in the macroscopic properties of LaCoO3. Around x ~ 0.125 the large maximum in alpha(T) has completely vanished. With further increasing x three different anomalies develop.
Turn this paper into a full lesson
ArcXiv compiles a staged curriculum from this paper: 8-12 lessons across beginner → advanced, synthesised section guides, visuals, flashcards, a quiz, exercises, and on-demand deep dives per section. Grounded in the abstract, never invented.