Densely Packed CO2 Aids Charge, Spin, and Lattice Ordering Partially Fluctuated in a Porous Metal–Organic Framework Magnet

Abstract

AbstractPartial charge fluctuations in the charge‐ordered state of a material, often triggered by structural disorders and/or defects, can significantly alter its physical characteristics, such as magnetic long‐range ordering. However, it is difficult to post‐chemically fix such accidental partial fluctuations to reconstruct a uniform charge‐ordered state. Herein, we report CO2‐aided charge ordering demonstrated in a CO2‐post‐captured layered magnet, [{Ru2(o‐ClPhCO2)4}2{TCNQ(OMe)2}] ⋅ CO2 (1⊃CO2; o‐ClPhCO2−=ortho‐chlorobenzoate; TNCQ(OMe)2=2,5‐dimethoxy‐7,7,8,8‐tetracyanoquinodimethane). Pristine porous layered magnet 1 had a partially charge‐fluctuated ordered state, which provided ferrimagnetic ordering at TC=65 K. Upon loading CO2, 1 adsorbed one mole of CO2, forming 1⊃CO2, and raising TC to 100 K. This was because of the vanishing charge fluctuations without significantly changing the framework structure. This research illustrates the post‐accessible host–guest chemistry delicately combined with charge, spin, and lattice ordering in a spongy magnet. Furthermore, it highlights how this innovative approach opens up new possibilities for technology and nanoscale magnetism manipulation.