dc.description.abstract
A thorough investigation into the role of the counterion and
occluded solvent on the structure and spin-crossover behaviour
of the threefold interpenetrated network [Fe(4ditz)3]2+
[4ditz = 1,4-bis(tetrazol-1-yl)butane] is presented. As seen by
X-ray single crystal diffraction, changing the hexafluorophosphate
anion in the previously investigated trigonal
phase [Fe(4ditz)3](PF6)2 to tetrafluoroborate causes the butylene
spacers to adopt three different conformations, whereupon
the symmetry is reduced to triclinic (space group P1¯).
X-ray powder diffraction and NMR spectroscopy provide evidence
for the incorporation of statistically distributed ethanol
molecules in the cavities of the compound, whose amount
Introduction
We have recently published structural and magnetic data
obtained from a series of spin crossover (SC) ditetrazole
complexes with alkylene bridges between the coordinating
tetrazoles [1,n-bis(tetrazol-1-yl)alkane]. The bridging carbon
chain was altered between n = 5-10 and 12 using BF4
-
and n = 4-10 and 12 with ClO4
- as anion. Absmeier et
al.,[1,2] showed, as expected, a decrease in Fe-Fe interactions
as the alkylene spacer is extended. This effect is ob-
[a] Department of Chemistry, University of Otago,
P. O. Box 56, Dunedin, New Zealand
Fax: +64-3-479-7906
E-mail: gjameson@chemistry.otago.ac.nz
[b] College of Science and Engineering, Aoyama-Gakuin University,
5-10-1 Fuchinobe, Sagamihara, Kanagawa 229-8558, Japan
[c] Institute of Applied Synthetic Chemistry, Vienna University of
Technology,
Getreidemarkt 9/163-AC, 1060 Vienna, Austria
Fax: +43-1-58801-16299
E-mail: wlinert@mail.zserv.tuwien.ac.at
[d] Institute for Solid State Physics, Vienna University of Technology,
Wiedner Hauptstraße 8-10/138, 1040 Vienna, Austria
[e] LAMM, Dipartimento di Chimica & UdR INSTM, Università
di Firenze,
Via della Lastruccia 3, 50019 Sesto F.no, Italy
[f] Institut de Chimie de la Matière Condensée de Bordeaux, UPR
CNRS No 9048, Université Bordeaux 1, Groupe des Sciences
Moléculaires,
87 Av. du Doc. A. Schweitzer, 33608 Pessac, France
Supporting information for this article is available on the
WWW under http://dx.doi.org/10.1002/ejic.200900537.
© 2009 Wiley-VCH Verlag 3948 GmbH & Co. KGaA, Weinheim Eur. J. Inorg. Chem. 2009, 3948-3959
depends on whether absolute ethanol or a binary system,
ethanol/water (95:5, v/v), is used as solvent. The phase precipitated
from EtOH/H2O features a metastable high-spin
(HS) state when rapidly cooled, a sharp spin transition to a
mixed HS/LS (1:1) state at around 90 K on slow cooling with
an approximately 10 K hysteresis and LIESST appears,
whereas the sample synthesised from absolute ethanol shows
a more gradual spin transition at the same temperature without
hysteresis.
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