Center for Molecular Modeling - F. Loncke

EPR and ENDOR analysis of Fe3+ impurity centers in fluoroelpasolite lattices

wim — Mon, 03 Oct 2011 07:13:34 +0000

F. Loncke, H. De Cooman, N.M. Khaidukov, H. Vrielinck, E. Goovaerts, P. Matthys, F. Callens

Physical Chemistry Chemical Physics (PCCP)

9 (39), 5320-5329

2007

Abstract

Fe3+ ions in hexagonal and cubic fluoroelpasolite crystals (AI2BIMIIIF6) have been investigated in a combined Electron Paramagnetic Resonance (EPR) and Electron Nuclear Double Resonance (ENDOR) study. A detailed analysis of the ENDOR spectra for the nearest 19F and 23Na shells in X (9.5 GHz) and Q band (34 GHz) allowed the complex EPR spectra to be disentangled and to determine the spin Hamiltonian parameters for the various S = 5/2 Fe3+ centres. W-band (95 GHz) EPR measurements as a function of temperature were performed to provide unambiguous evidence about the absolute signs of the Zero Field Splitting (ZFS) and SuperHyperFine (SHF) parameters for Fe3+ in Cs2NaAlF6 as already determined from the ENDOR work. It could be concluded that all principal 19F hyperfine values were positive, in agreement with earlier assignments in the literature for related systems. A comparative analysis of the 19F SHF data for Fe3+ at a perfectly octahedral site in the cubic crystal, and at two slightly trigonally distorted environments in the hexagonal crystals, indicates that the metal-to-ligand distance changes upon doping. The obtained set of parameters concerning one defect in various analogous environments can furthermore be used to test different methods of theoretical calculations for ZFS and SHF values.

DOI

http://dx.doi.org/10.1039/B704406B

Private attachment

07 phys. chem. chem. phys. 9 5320 loncke.pdf

Spectroscopic Study of Interactions Between Rare Earth Ions in Er-Doped Cs2NaYF6

wim — Tue, 18 Oct 2011 08:35:37 +0000

H. Vrielinck, I. Izeddin, F. Loncke, H. De Cooman, F. Callens, T. Gregorkiewicz

Poster

Conference / event / venue

2nd Aspect Workshop on Advanced Spectroscopy

Kazimierz Dolny, Poland

Thursday, 29 September, 2005 to Sunday, 2 October, 2005

ENDOR Analysis of Fe3+ Impurity Centres in Fluoroelpasolite Lattices

wim — Tue, 18 Oct 2011 08:17:56 +0000

F. Loncke, H. Vrielinck, H. De Cooman, N.M. Khaidukov, F. Callens

Poster

Conference / event / venue

39th Annual International Meeting of the ESR Group of the Royal Society of Chemistry: Advanced Techniques and Applications of EPR

Edinburgh, Schotland

Sunday, 2 April, 2006 to Wednesday, 5 April, 2006

Probing interactions between rare-earth ions in a Cs2NaY1-xErxF6 concentration series, a model system for wide-bandgap solids

wim — Mon, 17 Oct 2011 11:48:45 +0000

H. Vrielinck, I. Izeddin, T. Gregorkiewicz, H. De Cooman, F. Loncke, F. Callens, J. Lauwaert, P. Clauws

Talk

Conference / event / venue

E-MRS 2005 Spring Meeting

Strasbourg, France

Tuesday, 31 May, 2005 to Friday, 3 June, 2005

Field-frequency ENDOR spectroscopy of paramagnetic defects in insulating materials

wim — Mon, 17 Oct 2011 10:31:10 +0000

H. Vrielinck, F. Loncke, H. De Cooman, M.A. Tarpan, D. Zverev, P. Matthys, F. Callens

Talk

Conference / event / venue

16th International Conference on Defects in Insulating Materials (ICDIM) 2008

Aracaju, Brazil

Sunday, 24 August, 2008 to Friday, 29 August, 2008

ENDOR in field-frequency space: orientation, species and quantum state selection

wim — Mon, 17 Oct 2011 10:10:19 +0000

H. Vrielinck, F. Loncke, M.A. Tarpan, H. De Cooman, D. Zverev, F. Callens

Talk

Conference / event / venue

42nd Annual Meeting of the Electron Spin Resonance group of the Royal Society of Chemistry

Norwich, UK

Sunday, 19 April, 2009 to Thursday, 23 April, 2009

Abstract

ENDOR_Vrielinck 2009.pdf