Inorganic Chemistry
Communication
calculated bond distances are generally in good agreement with
the X-ray structure (see Supporting Information, Table S2).
The resulting spin density (Figure 4, left) is focused at the
ACKNOWLEDGMENTS
■
The authors thank Larry Henling and Michael Day for X-ray
structures and Angelo Di Bilio for assistance with EPR spectra.
We acknowledge Allen Oliver (University of Notre Dame) and
Jeannette Krause (University of Cincinati) for X-ray data
collection on 3 via the SCrALS program at Beamline 11.3.1,
Advanced Light Source (LBNL), supported by the U.S. DOE,
Energy Material Sciences Division. The Bruker KAPPA APEX
II was purchased via an NSF CRIF:MU. The authors thank
Nicole Fry for obtaining magnetic susceptibility data on 4.
Funding sources: NSF Grant CHE-0802907 (to M.J.R., J.R.W.,
and H.B.G.); NSF Grant CHE-1042009 (to M.J.R.); Grant
DOE-AC02-05CH11231 (synchrotron X-ray structure); NSF
Grant CHE-0639094 (Mo Kα X-ray structures).
1
Figure 4. DFT-calculated spin-density plots of 4 optimized at S = /2
5
(left) and /2 (right) configurations.
REFERENCES
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133.
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1.95 Å; see Supporting Information, Table S2), strongly
suggesting partial population of a high-spin FeIII center in the
solid state at 100 K. We performed a DFT calculation assuming
an S = 5/2 ground state, which more accurately reproduced the
crystallographically determined bond distances in the central
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5
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ASSOCIATED CONTENT
* Supporting Information
■
S
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CIF files for 1−4, crystal data for 1−4 (Table S1), bond
distances and angles for 1−4 (Table S2), DFT parameters
(Tables S3 and S4), spin densities of 4 (Table S5), CVs of 1
and 2 (Figures S1 and S2), additional ORTEP views of 3 and 4
(Figures S3 and S4), EPR spectra (Figure S5), and UV/vis
absorption spectrum of 4 (Figure S6). This material is available
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AUTHOR INFORMATION
Corresponding Author
(24) Collison, D.; Powell, A. K. Inorg. Chem. 1990, 29, 4735.
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Author Contributions
All authors have given approval to the final version of the
manuscript.
Notes
The authors declare no competing financial interest.
1982
dx.doi.org/10.1021/ic202253v | Inorg. Chem. 2012, 51, 1980−1982