Back to overview

Giant Pressure Dependence and Dimensionality Switching in a Metal-Organic Quantum Antiferromagnet

Type of publication Peer-reviewed
Publikationsform Original article (peer-reviewed)
Author Wehinger B., Fiolka C., Lanza A., Scatena R., Kubus M., Grockowiak A., Coniglio W. A., Graf D., Skoulatos M., Chen J.-H., Gukelberger J., Casati N., Zaharko O., Macchi P., Krämer K. W., Tozer S., Mudry C., Normand B., Rüegg Ch.,
Project New materials for honeycomb-lattice and single-ion magnets
Show all

Original article (peer-reviewed)

Journal Physical Review Letters
Volume (Issue) 121(11)
Page(s) 117201 - 117201
Title of proceedings Physical Review Letters
DOI 10.1103/physrevlett.121.117201


We report an extraordinary pressure dependence of the magnetic interactions in the metal-organic system ½CuF2ðH2OÞ22pyrazine. At zero pressure, this material realizes a quasi-two-dimensional spin-1=2 squarelattice Heisenberg antiferromagnet. By high-pressure, high-field susceptibility measurements we show that the dominant exchange parameter is reduced continuously by a factor of 2 on compression. Above 18 kbar, a phase transition occurs, inducing an orbital re-ordering that switches the dimensionality, transforming the quasi-two-dimensional lattice into weakly coupled chains. We explain the microscopic mechanisms for both phenomena by combining detailed x-ray and neutron diffraction studies with quantitative modeling using spin-polarized density functional theory.