[Cu(HF2)2(pyrazine)]n: A Rectangular Antiferromagnetic Lattice with a Spin Exchange Path Made Up of Two Different FHF Bridges


  • Work at EWU was supported by the National Science Foundation (NSF) under Grant No. DMR-1005825. Work at Argonne National Laboratory and North Carolina State University were supported by the Office of Basic Energy Sciences (BES), Division of Materials Sciences of the U.S. Department of Energy (DoE) under contract DE-AC02-06CH11357 and DE-FG02-86ER45259 and by the computing resources of the NERSC and HPC Centers. A portion of this work was performed at the National High Magnetic Field Laboratory, which is supported by the NSF Cooperative Agreement No. DMR-0654118, the State of Florida, and the U.S. DoE BES program “Science in 100 T.” This work was also supported by the EPSRC (UK). We gratefully acknowledge C. Baines (PSI) for technical assistance. We thank C. P. Landee for helpful discussions.


original image

The two-dimensional antiferromagnet [Cu(HF2)2(pyz)]n (pyz=pyrazine) has a rectangular lattice (see picture) displaying two types of FHF bridging modes. The spin exchange through Cu-(FHF)2-Cu is about 90 % stronger than through Cu-pyz-Cu, and the μ1,1-coordinated FHF, which is close in nature to F⋅⋅⋅HF, is largely responsible for the exchange. C black, Cu red, F green, H cyan.