Organic Ammonium Modulated Mixed-Valence Multiferroics Exhibiting Large Spontaneous Strain and Exchange Bias
Abstract
Three isotopological (stb) mixed-valence iron-formate frameworks, [A][FeIII(FeII)2(HCOO)9] (1-3), were constructed and exhibit ferroelastic phase transition with spontaneous strain of 0.16. 1-3 are spin-canted antiferromagnets with distinct TN from 26 K to 36 K and display exchange bias (EB) performance induced by the pinning of the spins at distinct sublattices.