ISBN: 978-83-60043-10-3 - eurobic9

Eurobic9, 2-6 September, 2008, Wrocław, Poland
P77. A Novel Technique to Probe the Inorganic and Bioinorganic
Chemistry of Lead: 204m Pb-PAC Spectroscopy
L. Hemmingsen a , J. Vibenholt b , M. Magnussen b , M. Stachura a , M. J. Bjerrum a ,
P. W. Thulstrup a
a
Department of Natural Sciences, University of Copenhagen, Denmark
e-mail: lhe@life.ku.dk
b
Department of Chemistry, University of Copenhagen, Denmark
Perturbed angular correlation of γ-rays (PAC) spectroscopy has been applied routinely in solid state physics over
the past 5 decades, and to a lesser extent in coordination chemistry and biochemistry using a variety of PAC
probes, providing information on the molecular and electronic structure in the vicinity of the PAC probe [1].
204m Pb-PAC spectroscopy was first applied in 1973 by Haas and Shirley [2], in investigations of inorganic
compounds such as PbCl2, PbFCl, PbI2, PbO, PbSO4, PbCrO4, PbC2O4, and Pb(SCN)2. Only recently the
technique was “revived” in an effort by the PAC-group in Leipzig, Germany, and the ISOLDE collaboration at
CERN [3], where additional inorganic compounds (PbCO3, Pb2O(CO3), Pb3(PO4)2, Pb(CN)2, PbO, Pb3O4,
Pb(IO3)2, PbBr2, PbTiO3) were investigated. No applications to coordination compounds nor applications in
biochemistry have been published yet in peer reviewed journals, although a convincing attempt to determine the
NQI in Pb(II)-substituted azurin was carried out in the Ph.D. work by Frank Heinrich [4].
In this work [5] we present the first application of 204m Pb-PAC spectroscopy to a coordination compound, in the
sense that it possesses a full molecular entity in the unit cell, see Figure 1, rather than the periodic crystalline
structure of the inorganic compounds investigated previously.
Figure 1 Left: The structure of [Pb(II) iso-maleonitriledithiolate] 4- ([6], counterions not shown). Right: the
Fourier tranform of the perturbation function recorded by 204m Pb-PAC spectroscopy (Thin line: data; boldfaced
line: fit).
Acknowledgements: The Danish Natural Science Research Council is acknowledged for funding, and
ISOLDE/CERN for beam time
References:
[1] Hemmingsen L., Sas K.N., Danielsen E. Chem. Rev. 2004, 104, 4027.
[2] Haas H., Shirley D. J. Chem. Phys. 1973, 58, 3339.
[3] Tröger W., Dietrich M., Araujo J.P., Correia J.G., Haas H., and the ISOLDE collaboration Z. Naturforsch.
2002, 57A, 586.
[4] Heinrich F., Ph.D. thesis, 2005, Faculty of Physics and Geosciences, University of Leipzig, Germany
[5] Vibenholt J., Magnussen M., Stachura M., Bjerrum M.J., Thulstrup P.W. and Hemmingsen L. in prep.
[6] Magyar J.S., Weng, T.-C., Stern C.M., Dye D.F., Rous B.W., Payne J.C., Bridgewater B.M., Mijovilovich
A., Parkin G., Zaleski J.M., Penner-Hahn J.E., and Godwin H.A. J. Am. Chem. Soc. 2005, 127, 9495
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