Quantum buckling in metal-organic framework materials

TL;DR

This paper explores quantum buckling phenomena in metal-organic frameworks, revealing strain-induced quantum phase transitions and novel ordered phases at low temperatures.

Contribution

It introduces a quantum mechanical model of buckling in MOFs, deriving a phase diagram with multiple quantum phases and transitions.

Findings

Quantum buckling exhibits superposition of degenerate states.

Strain induces quantum phase transitions between buckling phases.

New strain-induced quantum phases are identified.

Abstract

Metal organic frameworks are porous materials composed of metal ions or clusters coordinated by organic molecules. As a response to applied uniaxial pressure, molecules of straight shape in the framework start to buckle. Under sufficiently low temperatures, this buckling is of quantum nature, described by a superposition of degenerate buckling states. Buckling states of adjacent molecules couple in a transverse Ising type behavior. On the example of the metal organic framework topology MOF-5 we derive the phase diagram under applied strain, showing a normal, a parabuckling, and a ferrobuckling phase. At zero temperature, quantum phase transitions between the three phases can be induced by strain. This novel type of order opens a new path towards strain induced quantum phases.