Magnetism in Low-Dimensional Organic-Metal Halide Hybrids

Low-dimensional (LD) organic-metal halide hybrids (OMHHs) have recently emerged as new generation functional materials with exceptional structural and property tunability. Despite the remarkable advances in the development of LD OMHHs, optical properties have been the major functionality extensively investigated for most of LD OMHHs developed to date, while other properties, such as magnetic and electronic properties, remain significantly under-explored. Here, we report the studies of the magnetic and electronic properties of a series LD OMHHs, which exhibit distinct characteristics depending on the structures. For instance, zero-dimensional (0D) (C₂₄H₂₀P)₂MnCl₄, (C₂₄H₂₀P)₂FeCl₄, (C₂₄H₂₀P)₂CoCl₄, and (C₂₄H₂₀P)₂CuCl₄ hybrids are found to exhibit paramagnetic behavior, while one-dimensional (1D) (C₈H₂₂N₂)Cu₂Cl₆displaying antiferromagnetic ordering with a Néel temperature of 24K, owing to the antiferromagnetic coupling between Cu atoms through chloride bridges in 1D [Cu₂Cl₆^2-]_∞ chains. The arrangements of spins in 1D (C₈H₂₂N₂)Cu₂Cl₆ are confirmed by DFT calculations which reveals that the lowest energy structure contains Cu atoms with spins oriented anti-parallel to each other within the chain. The two-terminal (2T) electrical measurement on a (C₈H₂₂N₂)Cu₂Cl₆single crystal confirms its insulating nature. This work shows once again the exceptional tunability of LD OMHHs, which could serve as a highly promising tunable quantum material platform for spintronics.