title: Pressure-induced magnetic crossover driven by hydrogen bonding in CuF₂(H₂O)₂(3-chloropyridine).
abstract: Hydrogen bonding plays a foundational role in the life, earth, and chemical sciences, with its richness and strength depending on the situation. In molecular materials, these interactions determine assembly mechanisms, control superconductivity, and even permit magnetic exchange. In spite of its long-standing importance, exquisite control of hydrogen bonding in molecule-based magnets has only been realized in limited form and remains as one of the major challenges. Here, we report the discovery that pressure can tune the dimensionality of hydrogen bonding networks in CuF₂(H₂O)₂(3-chloropyridine) to induce magnetic switching. Specifically, we reveal how the development of O-H···Cl exchange pathways under compression combined with an enhanced ab-plane hydrogen bonding network yields a three dimensional superexchange web between copper centers that triggers a reversible magnetic crossover. Similar pressure- and strain-driven crossover mechanisms involving coordinated motion of hydrogen bond networks may play out in other quantum magnets.
authors.affiliation: Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996 USA.
authors.forename: Kenneth R
authors.initials: KR
authors.lastname: O'Neal
authors.affiliation: 1] Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996 USA [2] Department of Physics, University of Florida, Gainesville, FL 32611-8440, USA.
authors.forename: Tatiana V
authors.initials: TV
authors.lastname: Brinzari
authors.affiliation: Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996 USA.
authors.forename: Joshua B
authors.initials: JB
authors.lastname: Wright
authors.affiliation: 1] Geophysical Laboratory, Carnegie Institution of Washington, Washington D.C. 20015 USA [2] State Key Laboratory of Superhard Materials, Jilin University, Changchun 130012 China.
authors.forename: Chunli
authors.initials: C
authors.lastname: Ma
authors.affiliation: Physics Department, Virginia Commonwealth University, Richmond, Virginia 23284 USA.
authors.forename: Santanab
authors.initials: S
authors.lastname: Giri
authors.affiliation: 1] Materials Science Division, Argonne National Laboratory, Lemont, Illinois 60439 USA [2] Division of Materials Research, National Science Foundation, Arlington, Virginia 22230 USA.
authors.forename: John A
authors.initials: JA
authors.lastname: Schlueter
authors.affiliation: 1] Physics Department, Virginia Commonwealth University, Richmond, Virginia 23284 USA [2] Center for Applied Physics and Technology of Peking University, Beijing 100871, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Physics Department, Virginia Commonwealth University, Richmond, Virginia 23284 USA.
authors.forename: Puru
authors.initials: P
authors.lastname: Jena
authors.affiliation: Geophysical Laboratory, Carnegie Institution of Washington, Washington D.C. 20015 USA.
authors.forename: Zhenxian
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996 USA.
authors.forename: Janice L
authors.initials: JL
authors.lastname: Musfeldt