Organic Multiferroic Magnetoelastic Complexes

The design of crystal structures aids the discovery of interesting physical phenomena in organic crystals. In this work, the optimization of the coronene–tetracyanoquinodimethane (TCNQ) structure generates non‐degenerate energy levels of spin‐up and spin‐down electrons after charge transfer, producing spontaneous spin polarization, leading to pronounced ferromagnetism. The deformed crystal lattice can significantly affect the saturation magnetization of organic ferromagnets to present a remarkable magnetoelastic coupling. Furthermore, the magnetic‐field‐induced lattice shrinkage of the ferromagnetic crystals supports a spin–lattice‐interaction‐dependent magnetoelastic coupling. This concept of organic magnetoelastic coupling will pave the way for the rapid mechanical control of spin polarization in organic multiferroic magnetoelastic materials. The spin–lattice interaction is an intrinsic property of magnetoelastic coupling. In organic ferromagnetic crystals, the deformed crystal lattice changes the saturation magnetization of ferromagnets to exhibit a remarkable magnetoelastic coupling. Moreover, when stimulated by a magnetic field, the lattice of the ferromagnetic crystals shrinks. Organic magnetoelastic coupling is expected to be of great interest for ultrasensitive spin‐mechanical devices.