Linear Electric Shifts in the Paramagnetic Resonance of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">Al</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">O</mml:mi></mml:mrow><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>: C

Royce, E. B.; Bloembergen, N.

doi:10.1103/physrev.131.1912

Cited by 104 publications

(19 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It was indicated that δΓ or δD should be about 4 x 10 -7 cm-1 •(V/cm) -1 , in order to account for the peak value of α33. This magnitude of the latter should be compared with δD = 6 x 10-9 cm-1 •(V/cm) -1 , observed for Cr3+ ions in ruby [42].…”

Section: Case Of Cr2o3mentioning

confidence: 80%

“…Experimental data on uby were utilized for the discussion of the mechanism of the magnetoelectric effect in Cr2O3 with the same crystal structure [11,41]. The electronic origin was discussed of the electric field dependence of the spin Hamiltonian coefficients [42].…”

Section: Free Energy Of the Crystalmentioning

confidence: 99%

“…† Ham [79] analyzed the ESR data of Ludwig and Woodbery [40] on the interstitial transition metal eleinents in Si. Royce and Bloembergen [42] measured the electric shift of the spin Hainiltonian parameters of Cr 3 + in ruby and discussed its electronic origin. In both cases, it was concluded that the inain source of the effect is the inodification of the molecular orbitals of 3d electrons of the transition metal by the electric field.…”

Section: Case Of Ferromagnetsmentioning

confidence: 99%

See 2 more Smart Citations

Magnetoelectric Effect in Magnetic Materials

1992

View full text Add to dashboard Cite

Magnetoelectric effect in magnetic insulators is reviewed. Alter an intuitive explanation of the effect in antiferromagnetic Cr 2 O3, the following topics are discussed on the experiments. Measurement and controlling of antiferromagnetic domains as well as antiferromagnetic domain wall motion. Expansion of the free energy of crystals in terms of magnetic and electric fields and polarizations. Information on the magnetic symmetry of crystals. Investigation of mechanisms of magnetoelectric effect. Excited states and optical observation.

show abstract

Section: Case Of Cr2o3mentioning

confidence: 80%

Section: Free Energy Of the Crystalmentioning

confidence: 99%

Section: Case Of Ferromagnetsmentioning

confidence: 99%

See 1 more Smart Citation

Magnetoelectric Effect in Magnetic Materials

1992

View full text Add to dashboard Cite

show abstract

“…The EPR parameters of a sample can often be modified by applying an electric field across it (15). These shifts are small, but have been observed in several cases for single-crystal materials (16).…”

Section: Methodsmentioning

confidence: 99%

Linear Electric Field-Induced Shifts in Electron Paramagnetic Resonance: A New Method for Study of the Ligands of Cytochrome P-450

Peisach

Mims²

1973

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

The linear electric field shift in paramagnetic resonance has, for the first time, been observed in frozen solutions. The magnitude of the shift parameters, measured at g.. of the electron paramagnetic resonance absorption envelope,_ has been used to characterize lowspin ferric heme mercaptide complexes where the nonmercaptide liganid was varied. The magnitude of the shift provides a measure of the difference between the crystal field contribution of the mercaptide and nonmercaptide ligands. In low-spin ferric cytochrome P-450 of rat liver, the presence of an electric field shift indicates a deviation from inversion symmetry and proves that the axial ligands to the heme are not the same. From the magnitude of the shift and its dependence upon the angle between applied electric and magnetic fields, it is suggested that the nonaxial ligand to the heme has a crystal field contribution greater than imidazole and smaller than guanidine.Cytochrome P450 represents a class of heme proteins characterized by an unusual optical absorption when reduced and reacted with CO (1, 2). Various members of this class have been isolated from bacteria (3, 4) and mammals (5, 6), but cytochrome P450 found in the endoplasmic reticulum of mammalian liver [and which is the terminal oxidase of the xenobiotic hydroxylating systems (7) ] has drawn the greatest attention.In liver slices and liver microsomes, cytochrome P450 is found largely in the low-spin ferric state and can therefore be studied by electron paramagnetic resonance (EPR) spectroscopy (7,8). On the basis of magnetic resonance comparison with model compounds, it has been suggested that a necessary z ligand to heme of all cytochromes P450, irrespective of their sources, is a mercaptide sulfur, endogenous to the protein structure and most likely from a cysteinyl residue (9, 10). The nature of the nonmercaptide z ligand in the various cytochromes P450 remains unknown, although EPR examination suggests a heterogeneity of structures, at least in soluble preparations from liver microsomes (11, 12).It is, however, the presence of the mercaptide ligand in cytochrome P450 that essentially determines the EPR behavior. It is difficult to make structural assignments on the basis of EPR, as was done for various low-spin heme proteins (9, 13), since the second z ligand has only a minor effect on the g tensor.In this preliminary report we describe a new technique that makes it possible to investigate cases of this kind. Specifically, we have observed for the first time a linear electric fieldinduced shift in the EPR frequency of low-spin ferric cytochrome P-450 from rat-liver microsomes of a phenobarbitaltreated animal and also of several heme mercaptide model compounds in frozen solution. In this way we were able to characterize the deviations from inversion symmetry of the center composed of the heme group and the ligands in these materials and to show that there is a marked difference in the bonding strengths of the two z ligands in the heme protein. In consideration of the magnitu...

show abstract

“…Unfortunately, there are insufficient data to re-analyse the results in terms of electric field or strain effects. In order of magnitude, spin-resonance methods should be able to detect fields of order lo4 V cm-' (see Ludwig and Ham 1963, Royce and Bloembergen 1963, Mims and Gillen 1966.…”

Section: Discussionmentioning

confidence: 99%

Broadening of resonance lines by charged dislocations

Stoneham¹

1974

J. Phys. C: Solid State Phys.

View full text Add to dashboard Cite

Abstract. It is shown that the random electric fields of charged dislocations in insulators should cause appreciable broadening of sharp resonance lines such as spin-resonance signals. The degree of broadening is very sensitive to the screening of the dislocations by charged point defects. Since the shape of the inhomogeneously broadened resonance line monitors the distribution of the internal fields, the lineshape can be used to deduce properties of the charged dislocations, like their charge per unit length and the degree of screening. Quantitative calculations are presented which suggest that spectroscopic methods, notably spin resonance, should provide a convenient method of investigating charged dislocations.

show abstract

Linear Electric Shifts in the Paramagnetic Resonance ofAl2O3: C

Abstract: It is shown that the spin Hamiltonian for Cr 3+ ions in the AI2O3 lattice has to be augmented by a term 2J»-%j Show more

Cited by 104 publications

References 44 publications

Magnetoelectric Effect in Magnetic Materials

Magnetoelectric Effect in Magnetic Materials

Linear Electric Field-Induced Shifts in Electron Paramagnetic Resonance: A New Method for Study of the Ligands of Cytochrome P-450

Broadening of resonance lines by charged dislocations

Contact Info

Product

Resources

About