We performed electron spin resonance (ESR) studies of the mixed valence Prussian blue analogue,Rb0.8Mn1.1 [Fe(CN)6]·D2O in a wide frequency (9.5-319 GHz) and temperature (3.5-300 K) interval. Evidence for the proposed high-temperature Mn2+ (S = frac(5, 2))-NC-Fe3+ (S = frac(1, 2)) to low-temperature Mn3+ (S=2)-NC-Fe2+ (S=0) internal charge transfer has been detected: a characteristic reduction of χESRT on cooling from room temperature to 100 K, a particular frequency dependence of the room temperature ESR linewidth, and the temperature dependence of the ESR linewidth. Short-range magnetic correlations, reflected in a large broadening and dramatic shift of the ESR signal develop just above TC=10 K. Below TC, both the linewidth and the shift in position mimic the temperature dependence of the order parameter. In a quench experiment TC was reduced by 3 K. The observed ferromagnetic ordering arises from Mn3+ (S=2) moments in the low-temperature electronic configuration.
- Magnetic transition
- Structural transformation
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics