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  • Electronic structures of highly symmetrical compounds of f elements. 35 [1]: Crystal and molecular structure of tris(hydrotris(1-pyrazolyl)borato)lanthanide(III) (LnTp(3); Ln = La, Eu), and electronic structure of EuTp(3)

Abstract

In contrast to the result of a previous luminescence measurement but in accordance with previous IR and FIR spectroscopic investigations the Eu{3+} central ion of tris(hydrotris(1-pyrazolyl)borato)europium(III) (EuTp(3)) is coordinated according to a single crystal X-ray analysis in first coordination sphere by nine N atoms in the shape of a tricapped trigonal prism, resulting in an effective crystal field(CF) of symmetry D(3h). However, if one considers the whole molecule, molecular C(3h) symmetry is present in the crystal. This also holds for the corresponding La compound. The absorption spectrum of powdered EuTp(3) was recorded at approximately 5 K, and the luminescence spectrum at 77 K. On the basis of these optical spectra, an experimental CF splitting pattern has been derived, which comprises a sequence of energy levels of Gamma(4) and Gamma(6) symmetry, respectively. Sign and absolute value of the CF parameter B2/0 have been derived on an experimental basis, and model calculations adopting the approximations of electrostatic point charge and angular overlap models, respectively, predict negative values for the CF parameters B4/0 and B6/0. Keeping these signs, the experimentally derived truncated CF splitting pattern of EuTp(3) could be reproduced by fitting the free parameters of a phenomenological Hamiltonian.

Additional information

Authors: APOSTOLIDIS C, European Commission, Joint Research Centre, Institute for Transuranium Elements, Karlsruhe (DE);REBIZANT J, European Commission, Joint Research Centre, Institute for Transuranium Elements, Karlsruhe (DE);WALTER O, Institut für Technische Chemie, Forschungszentrum Karlsruhe, Karlsruhe (DE);KANELLAKOPOULOS B, Institut für Technische Chemie, Forschungszentrum Karlsruhe, Karlsruhe (DE);REDDMANN H, Institut für Anorganische und Angewandte Chemie, Universität Hamburg (DE);AMBERGER H-D, Institut für Anorganische und Angewandte Chemie, Universität Hamburg (DE)
Bibliographic Reference: An article published in: Zeitschrift für anorganische und allgemeine Chemie, Volume 628, Issue 9-10, (2002) Pp.2013-2025
Availability: This article can be accessed online by subscribers, and can be ordered online by non-subscribers, at: http://www3.interscience.wiley.com/cgi-bin/abstract/98517797/START
Record Number: 200215701 / Last updated on: 2003-01-09
Category: PUBLICATION
Original language: de
Available languages: de