Electron spin resonance in situ observation of the bending stress process in corundum materials and glasses

Stoêsser, R.; Steinfeldt, Norbert; Brenneis, Rudolf; Nofz, Marianne

doi:10.1007/bf00357846

Cited by 6 publications

(3 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Many different parameter sets describing the EPR spectrum of Fe 3+ in alumina can be found in the literature [10,25,26]. The simulations presented in the following were obtained using the parameter set published recently by Morin and Bonnin [10] given in table 1.…”

Section: Calculated Epr Spectra: α-Al 2 O 3 :Fe 3+mentioning

confidence: 99%

Electron paramagnetic resonance investigations of -Al₂O₃powders doped with Fe³ions: experiments and simulations

Buzaré

Silly

Klein

et al. 2002

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

Electron paramagnetic resonance (EPR) of Fe 3+ ions in Al 2 O 3 is studied in powder samples prepared by different routes and/or modified by thermal or mechanical treatments, with different doping levels and grain sizes. The measurements are performed in various frequency bands (S, X, K, Q and W) and with bimodal detection in X-band. Simulations of the spectra are achieved with a code designed for computing EPR powder spectra described by any spin Hamiltonian including second-, fourth-and sixth-order ZFS terms (S 7/2). The linewidths, intensities and lineshapes are accounted for. The lineshape is Gaussian at low Fe 3+ concentration whereas it is Lorentzian for higher concentration. The linewidths are interpreted as the superimposition of three main contributions: intrinsic linewidth, dipolar broadening and broadening due to lattice imperfections. The latter is tentatively interpreted in terms of quadrupolar spin Hamiltonian parameter distributions treated using firstorder perturbation theory. Whatever the sample, only the b 2 2 spin Hamiltonian parameter is found to be distributed around a mean zero value which corresponds to rhombic distortions. Angle and bond length distributions are tentatively extracted from the b 2 2 distributions which gives some insight into the local order around the spin probe in relation to the preparation and treatment of the samples.

show abstract

Section: Calculated Epr Spectra: α-Al 2 O 3 :Fe 3+mentioning

confidence: 99%

Electron paramagnetic resonance investigations of -Al₂O₃powders doped with Fe³ions: experiments and simulations

Buzaré

Silly

Klein

et al. 2002

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

show abstract

“…la), even the high-field transitions (B 0 > 0.33 T, see Fig. la) react very sensitive on small structural changes in the bulk orat the surface of the crystallites [5].…”

Section: Esr Fine Structure Of Fe 3+ Ions Incorporated Into Crystallimentioning

confidence: 99%

“…narrow transitions could be registered up to field positions of B 0 ~ 0.4 T. The whole powder spectrum could be reproduced by simulation using the zero-field splitting parameter D = 5032 MHz and the cubic splitting constant a = 686 MHz (g = 2)[5]. It should be noted that in relative pure and well crystallized ~…”

mentioning

confidence: 99%

ESR evidence of order/disorder transitions in solids caused by dehydration

Stößer

Scholz

1997

Appl. Magn. Reson.

View full text Add to dashboard Cite

ESR spectroscopy was used to study order/disorder phenomena in paramagnetically doped solids. The dehydration process of alurninium fluoride and oxide hydrates and aluminosilicates was examined by ESR in situ measurements as well as using thermoanalytically quenched samples. Two types of amorphous states of solids have been studied: inorganic glasses in the conventional sense and amorphous states of solids which have not passed the liquid state. The complete ESR fine structure pattern of Fe 3 § ions is susceptible with respect to order/disorder processes of the actual host matrix. Dehydration processes bear some model character in this field. A quantitative description of the disorder effects on the Fe 3 § ESR could be given on the basis of a complete spin Hamiltonian using distributions of the fourth order spin coupling parameters.

show abstract

On the nature and role of Fe³⁺ ions in oxide and fluoride glasses

Stößer

Scholz

Nofz

et al. 1996

Ber Bunsenges Phys Chem

Self Cite

View full text Add to dashboard Cite

Fe3+ doped oxide and fluoride glasses were investigated by ESR spectroscopy at 4.2 K. For the first time, the resulting complex spectra could be completely reproduced starting from a diagonalization of the S = 5/2 spin‐hamiltonian, including the appropriate zero‐field splitting components D and E, and using distributions for the fourth order spin coupling parameters. By careful analysis of the differentiated and integrated experimental and calculated spectra it could be shown, that if only Fe3+ point defects are present in glasses, the main ESR intensity covers the range of g'∼4.3. Since all experimental spectra yield remarkable contributions in the range of g'∼2 there is evidence for the existence of magnetically interacting clusters in the glasses. Differences between Fe3+ doped oxide and fluoride glasses essentially concern the concentration dependent spectral pattern and the low‐temperature spin relaxation behaviour.

show abstract

Electron spin resonance in situ observation of the bending stress process in corundum materials and glasses

Cited by 6 publications

References 6 publications

Electron paramagnetic resonance investigations of -Al₂O₃powders doped with Fe³ions: experiments and simulations

Electron paramagnetic resonance investigations of -Al₂O₃powders doped with Fe³ions: experiments and simulations

ESR evidence of order/disorder transitions in solids caused by dehydration

On the nature and role of Fe³⁺ ions in oxide and fluoride glasses

Contact Info

Product

Resources

About

Electron spin resonance in situ observation of the bending stress process in corundum materials and glasses

Cited by 6 publications

References 6 publications

Electron paramagnetic resonance investigations of -Al2O3powders doped with Fe3 ions: experiments and simulations

Electron paramagnetic resonance investigations of -Al2O3powders doped with Fe3 ions: experiments and simulations

ESR evidence of order/disorder transitions in solids caused by dehydration

On the nature and role of Fe3+ ions in oxide and fluoride glasses

Contact Info

Product

Resources

About

Electron paramagnetic resonance investigations of -Al₂O₃powders doped with Fe³ions: experiments and simulations

Electron paramagnetic resonance investigations of -Al₂O₃powders doped with Fe³ions: experiments and simulations

On the nature and role of Fe³⁺ ions in oxide and fluoride glasses