One-Dimensional Magnetic MX 3 Single-Chains (M = Cr, V and X = Cl, Br, I).

Magnetic materials in reduced dimensions are not only excellent platforms for fundamental studies of magnetism, but they play crucial roles in technological advances. The discovery of intrinsic magnetism in monolayer two-dimensional van der Waals systems has sparked enormous interest, but the single-chain limit of one-dimensional magnetic van der Waals materials has been largely unexplored. Here, we report on a family of one-dimensional magnetic van der Waals materials with composition MX 3 (M = Cr, V, and X = Cl, Br, I), prepared in fully-isolated fashion within the protective cores of carbon nanotubes. Atomic-resolution scanning transmission electron microscopy identifies unique structures that differ from the well-known 2D honeycomb lattice MX 3 structure. Density functional theory (DFT) calculations reveal charge-driven reversible magnetic phase transitions. This article is protected by copyright. All rights reserved.