Synthesis and Magnetic Properties of the Multiferroic [C(NH<sub>2</sub>)<sub>3</sub>]Cr(HCOO)<sub>3</sub> Metal–Organic Framework: The Role of Spin–Orbit Coupling and Jahn–Teller Distortions
Kunihiro Yananose, Ewan R. Clark, Paul J. Saines, Paolo Barone, Alessandro Stroppa, Jaejun Yu
Abstract
High Resolution Image Download MS PowerPoint Slide We report for the first time the synthesis of [C(NH 2 ) 3 ]Cr(HCOO) 3 stabilizing Cr 2+ in formate perovskite, which adopts a polar structure and orders magnetically below 8 K. We discuss in detail the magnetic properties and their coupling to the crystal structure based on first-principles calculations, symmetry, and model Hamiltonian analysis. We establish a general model for the orbital magnetic moment of [C(NH 2 ) 3 ]M(HCOO) 3 (M = Cr, Cu) based on perturbation theory, revealing the key role of the Jahn–Teller distortions. We also analyze their spin and orbital textures in k -space, which show unique characteristics.