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Title: Pressure-driven orbital reorientations and coordination-sphere reconstructions in [CuF2(H2O)2(pyz)]

Abstract

Successive reorientations of the Jahn-Teller axes associated with the Cu{sup II} ions accompany a series of pronounced structural transitions in the title compound, as is shown by X-ray crystallography and high-frequency EPR measurements. The second transition forces a dimerization involving two thirds of the Cu{sup II} sites due to ejection of one of the water molecules from the coordination sphere

Authors:
; ; ; ; ; ; ; ;  [1];  [2];  [2];  [2];  [2]
  1. (Materials Science Division)
  2. (
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1047450
Report Number(s):
ANL/MSD/JA-72655
Journal ID: ISSN 0570-0833; ACIEAY; TRN: US201216%%295
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Angewandte Chemie. International Edition in English; Journal Volume: 51; Journal Issue: 30
Country of Publication:
United States
Language:
ENGLISH
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CHEMISTRY; COPPER; CRYSTALLOGRAPHY; DIMERIZATION; SPECTROSCOPY; WATER

Citation Formats

Prescimone, A., Morien, C., Allan, D., Schlueter, J., Tozer, S., Manson, J. L., Parsons, S., Brechin, E. K., Hill, S., EaStCHEM School of Chem.), Florida State Univ.), Harwell Sci. Innovation Campus), and Eastern Washington Univ.). Pressure-driven orbital reorientations and coordination-sphere reconstructions in [CuF2(H2O)2(pyz)]. United States: N. p., 2012. Web. doi:10.1002/anie.201202367.
Prescimone, A., Morien, C., Allan, D., Schlueter, J., Tozer, S., Manson, J. L., Parsons, S., Brechin, E. K., Hill, S., EaStCHEM School of Chem.), Florida State Univ.), Harwell Sci. Innovation Campus), & Eastern Washington Univ.). Pressure-driven orbital reorientations and coordination-sphere reconstructions in [CuF2(H2O)2(pyz)]. United States. doi:10.1002/anie.201202367.
Prescimone, A., Morien, C., Allan, D., Schlueter, J., Tozer, S., Manson, J. L., Parsons, S., Brechin, E. K., Hill, S., EaStCHEM School of Chem.), Florida State Univ.), Harwell Sci. Innovation Campus), and Eastern Washington Univ.). Mon . "Pressure-driven orbital reorientations and coordination-sphere reconstructions in [CuF2(H2O)2(pyz)]". United States. doi:10.1002/anie.201202367.
@article{osti_1047450,
title = {Pressure-driven orbital reorientations and coordination-sphere reconstructions in [CuF2(H2O)2(pyz)]},
author = {Prescimone, A. and Morien, C. and Allan, D. and Schlueter, J. and Tozer, S. and Manson, J. L. and Parsons, S. and Brechin, E. K. and Hill, S. and EaStCHEM School of Chem.) and Florida State Univ.) and Harwell Sci. Innovation Campus) and Eastern Washington Univ.)},
abstractNote = {Successive reorientations of the Jahn-Teller axes associated with the Cu{sup II} ions accompany a series of pronounced structural transitions in the title compound, as is shown by X-ray crystallography and high-frequency EPR measurements. The second transition forces a dimerization involving two thirds of the Cu{sup II} sites due to ejection of one of the water molecules from the coordination sphere},
doi = {10.1002/anie.201202367},
journal = {Angewandte Chemie. International Edition in English},
number = 30,
volume = 51,
place = {United States},
year = {Mon Jul 23 00:00:00 EDT 2012},
month = {Mon Jul 23 00:00:00 EDT 2012}
}
  • We have performed elastic and inelastic neutron scattering experiments on single crystal samples of the coordination polymer compound CuF{sub 2}(H{sub 2}O){sub 2}(pyz) (pyz = pyrazine) to study the magnetic structure and excitations. The elastic neutron diffraction measurements indicate a collinear antiferromagnetic structure with moments oriented along the [0.7 0 1] real-space direction and an ordered moment of 0.60 {+-} 0.03 {micro}B/Cu. This value is significantly smaller than the single-ion magnetic moment, reflecting the presence of strong quantum fluctuations. The spin wave dispersion from magnetic zone center to the zone boundary points (0.5 1.5 0) and (0.5 0 1.5) can bemore » described by a two-dimensional Heisenberg model with a nearest-neighbor magnetic exchange constant J{sub 2D} = 0.934 {+-} 0.0025 meV. The interlayer interaction J{sub perp} in this compound is less than 1.5% of J{sub 2D}. The spin excitation energy at the (0.5 0.5 0.5) zone boundary point is reduced when compared to the (0.5 1 0.5) zone boundary point by {approx}10.3% {+-} 1.4%. This zone boundary dispersion is consistent with quantum Monte Carlo and series expansion calculations for the S=1/2 Heisenberg square lattice antiferromagnet, which include corrections for quantum fluctuations to linear spin wave theory.« less
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