Fig. 2: Temperature-dependent lattice parameters and JT distortion.

a The substructure of an orthorhombic PMON with the longest, mediate, and shortest Mn-O bonds as indicated by dl, dm, and ds, respectively. The Mn-O-Mn bond angles are marked by γ and β. b The Mn-O-Mn bond lengths dl, dm, and ds of PMOA. c The Mn-O-Mn bond lengths of PMON (Phase1 and Phase2). d The Mn-O-Mn bond angles β. e The Mn-O-Mn bond angles γ. f JT distortion δ. Phase 1 of PMON experienced a jump in β and γ and a sudden drop in δ beyond 900 K. Mn atoms (large size) in purple, O atoms (small size) in blue/orange. The green/orange colored background represents a gradual change in temperature from low to high. Source data are provided as a Source Data file.