An Appraisal of the Understanding Pressure Effects on Structural, Optical, and Magnetic Properties of CsMnF4 and Other 3dn Compounds

A recent theoretical study of CsMnF4 under pressure [Inorg. Chem. 2024, 63(29), 13231] presents conclusions on its structural, optical, and magnetic behavior that conflict with established experimental evidence. Crucially, this work omits key prior experimental results on CsMnF4 and related Mn3+ fluorides under pressure. This perspective examines the resulting discrepancies, arguing that the omissions of this data undermines the theoretical estimates and methodological validity of Ref. [1]. This paper provides a critical overview centered on two main points: the contested nature of the pressure-induced high-spin to low-spin transition observed in CsMnF4 at ~37 GPa and a detailed discussion of Jahn-Teller physics in this archetypal system. By reconciling the existing literature with the new theoretical claims, this work aims to clarify the high-pressure behavior of CsMnF4.