SmallTalks "Quantum buckling in metal−organic frameworks"

Abstract 

Metal-organic frameworks are porous materials composed of metal ions or clusters connected by organic linkers. In response to applied strain, the linkers can buckle, similar to the deformation of a column under load. However, unlike a macroscopic column, the molecular linkers obey the laws of quantum mechanics, which allows for tunneling between different buckling configurations. In addition to tunneling, interactions between linkers, which depend on their buckling states, also have to be considered. To describe the collective buckling of many linkers, we adopt a model from magnetism, the transverse-field Ising model. This reveals two competing phases: ferrobuckling, where interactions dominate and linkers buckle cooperatively in the same direction, and parabuckling, where tunneling dominates and linkers remain in a superposition of buckling states.