Paramagnetic Resonance Of Mn2 Research Articles

Local zincblende coordination in heteroepitaxial wurtzite Zn1−xMgxO:Mn thin films with 0.01 ≤ x ≤ 0.04 identified by electron paramagnetic resonance

Heteroepitaxial Zn1−xMgxO:Mn thin films show already atx= 0.01 a local cubic zincblende coordination attributed to stacking faults.

Ferroelastic phase transition inK3Na(CrO4)2 single crystals: an electron paramagnetic resonance study

The phase transition in K3Na(CrO4)2 single crystals has been studied by electron paramagnetic resonance (EPR) ofMn2+ ions. The values of the spin-Hamiltonian parameters have beenevaluated. Below the phase transition temperature, the magneticz-axis is deflected in ac and bc crystallographic planes by the same angle. Anomalous lineshapes recorded below the phase transition temperature suggest the existence of anincommensurate phase.

Fir magnetospectroscopy on (CuIn)1−xMn2xTe2

The paramagnetic resonance of Mn2+ in the diluted magnetic semiconductor (CuIn)1−xMn2xTe2 was observed in a pulsed magnetic field up to 15 T at temperatures ranging from 4.2 K to 45 K. The temperature dependence of the line width of the paramagnetic resonance in (CuIn)1−xMn2xTe2 resembles the behaviour of other diluted magnetic semiconductors. A Dzyaloshinski-Moriya exchange constant of approximately 0.62 K was derived. This value fits well with the values reported for II–VI based diluted magnetic semiconductors [1], if we consider the larger degree hybridization of the 3d electrons with the band electrons in chalcopyrite semiconductors.

Host spin-lattice relaxation narrowing and the electron paramagnetic resonance of Mn(II) in single crystals of hexakis(pyridineN-oxide)cobalt(II) complexes

The electron paramagnetic resonance spectra of Mn(C5H5NO)6. X2 (X ≡ ClO- 4, BF- 4 and NO- 3) doped in single crystals of isomorphous paramagnetic Co(C5H5NO)6. X2 are studied at various temperatures. Zero-field splitting in all three crystals is axially symmetric and the magnitude of D is unusually large for an octahedral coordination polyhedron with all ligands identical. The sharp resonance of Mn(II) in the paramagnetic host observed at high temperatures is interpreted in terms of random modulation of the dipolar interaction between the guest Mn(II) and host Co(II) ions by the rapid spin-lattice relaxation of Co(II). The spin-lattice relaxation times of Co(II) ions at 300 K, estimated from the temperature dependent linewidth of the Mn(II) resonance, are 24 × 10-12, 28 × 10-12 and 23 × 10-12 s in perchlorate, fluoborate and nitrate crystals respectively. The temperature dependence of the relaxation is of the form 1/(at + bt 5) and below 270 K the direct process dominates.

Raman scattering from vibrational and electronic excitations in a II-VI quaternary compound: Cd1-x-yZnxMnyTe.

The Raman scattering in a II-VI quaternary compound (${\mathrm{Cd}}_{1\mathrm{\ensuremath{-}}\mathit{x}\mathrm{\ensuremath{-}}\mathit{y}}$${\mathrm{Zn}}_{\mathit{x}}$${\mathrm{Mn}}_{\mathit{y}}$Te) exhibits zone-center optical phonons whose frequencies vary with composition in a manner amenable to an extension of the modified random-element isodisplacement model. As a member of diluted magnetic semiconductors, ${\mathrm{Cd}}_{1\mathrm{\ensuremath{-}}\mathit{x}\mathrm{\ensuremath{-}}\mathit{y}}$${\mathrm{Zn}}_{\mathit{x}}$${\mathrm{Mn}}_{\mathit{y}}$Te exhibits the characteristic large magnetic-field-dependent redshift of the excitonic photoluminescence, the Raman-electron paramagnetic resonance of ${\mathrm{Mn}}^{2+}$, and an evidence of the Raman-antiferromagnetic resonance.

Electron paramagnetic resonance of Mn2+ in Ce2 Zn3 (NO3)12.24H2O single crystals

Electron paramagnetic resonance of Mn2+ in Ce2 Zn3 (NO3)12.24H2O single crystals has been studied in X-band at 290 and 90K. Mn2+ substitutes for Zn2+ sites. The spin-Hamiltonian parameters are evaluated.

Linear electric shift in the paramagnetic resonance of Mn 2+ in ZnTe

The influence of an electric field on the EPR transition has been observed in ZnTe:Mn 2+ at 29 K by applying an ac electric field. The value of the component of the third rank tensor describing the effect is R 14 = 164 Hz V -1 cm. A strong correlation between the magnitude of the component R 14 and the amount of covalency was found.

Linear electric shift in the paramagnetic resonance of Mn 2+ in CdTe

The influence of an electric field on the EPR transition has been observed for divalent manganese in cubic CdTe ar 10 K by applying an ac electric field. The value of the component of the third rank tensor describing the effect is R 14 = 110 Hz V −1 cm. The contribution of the piezoelectric deformation has been calculated.

EPR Study of Mn2+ in Hg(ClO4)2 · 6H2O Single Crystals

Abstract The electron paramagnetic resonance of Mn2+ in Hg(ClO4)2 · 6H2O has been studied at X-band at 298 K and 77 K. Mn2+ is found to substitute Hg 2+ . The spectra have been analysed using the spin-Hamiltonian appropriate for trigonal symmetry. From the unequal separations between the Δm = ± 1 doublets in M = + 1/2 → - 1/2 transitions, the value of the axial part of the quadrupole coupling constant is determined. The observed doublet separations of forbidden hyperfine transitions in M = + 1/2 → - 1/2 are in good agreement with those cal-culated.

Host Spin-Lattice Relaxation Narrowing in Pr2Co3(NO3)12 · 24 H2O: Mn2+ \ Gd3+ Single Crystals

Abstract Electron paramagnetic resonance of Mn2+ and Gd3+ in single crystals of Pr2Co3(NO3)12 · 24 H2O has been studied at X-band at 305 and 77 K. Mn2+ substitutes at two types of Co2+ sites whereas Gd3 substitutes at the single type of Pr3+ site in the lattice. The spin-Hamiltonian parameters have been evaluated. Observation of resolved Mn2+ and Gd3+ spectra at 305 K and their broadening on lowering the temperature are discussed in terms of host spin-lattice relaxation narrowing.

Paramagnetic resonance of Mn2+ in Na2S single crystals

Paramagnetic resonance of Mn2+ in Na2S single crystals

Electron paramagnetic resonance study of Mn2+ doped Mg(ClO4)2∙6H2O

Electron paramagnetic resonance of Mn2+ doped Mg(ClO4)2∙6H2O crystals has been studied from room temperature (300 K) down to liquid nitrogen temperature at X-band. The room temperature results show three inequivalent sites for Mn2+ in the crystal. Hyperfine forbidden transitions are observed when the magnetic field is not oriented along one of the principal axes. Two structural phase transitions have been observed at temperatures of 272 ± 1 and 103 ± 1 K, respectively. The transition occurring at 272 ± 1 K has been observed for the first time. The transition occurring at 103 ± 1 K is the one detected earlier through Mössbauer studies.

Electron paramagnetic resonance of Mn2+ and Gd3+ in Pr2Zn3(NO3)12.24 H2O single crystals

The electron paramagnetic resonance of Mn2+ and Gd3+ doped in Pr2Zn3(NO3)12.24H2O single crystals has been studied at X-band. Mn2+ substitutes for two Zn2+ sites, while Gd3+ substitutes for single type of Pr3+ sites. The spin-Hamiltonian analysis of the EPR spectra is presented at 298 K as well as 77 K.

Electron paramagnetic resonance of Mn2+in single crystals of hexaquonitrates of nickel and magnesium

An EPR study has been carried out on Mn2+-doped single crystals of hexaquonitrates of Mg and Ni, Mg(OH2)6.(NO3)2 and Ni(OH2)6.(NO3)2, at room temperature ( approximately 300K) and at X-band. Mn2+ substituting for Mg2+ in Mg(OH2)6.(NO3)2 exhibits two identical, but differently oriented, magnetic complexes, whose z axes make an angle of approximately 15+or-1 degrees with each other in the zx plane. However, Mn2+-doped Ni(OH2)6.(NO3)2 crystals exhibit only one single thirty-line spectrum indicating the equivalency of two Ni(OH2)62+ complexes per unit cell. The EPR spectra are analysed using a spin-Hamiltonian of orthorhombic symmetry to get the best fit parameters. These studies reveal that the two crystals are not isomorphous and that the site symmetry at the cation sites is very low.

Effect of H on the paramagnetic resonance of Mn in Pd

The authors report the results of measurements of the paramagnetic resonance of manganese in palladium and hydrogenated Pd. In the alpha , beta mixed phase region the authors observe two distinct resonances indicating a difference in density of states in the two phases. The results are discussed in terms of recent superconductivity and magnetic ordering measurements.

Electron paramagnetic resonance of Mn2 in the ferroelectric phase of NaNO2

The electron paramagnetic resonance of Mn2+ ion doped in single crystals of sodium nitrite (NaNO2) has been studied at 9.5 kmc from room temperature (∼27°C) to 180°C. Only one magnetic complex of Mn2+ has been found. The complex gives different spectra in the ferro- and para-electric phases of the host crystal. The resonance lines of the allowed transitions at room temperature have been fitted to a spin-Hamiltonian of orthorhombic symmetry. The resonance lines show a strong angular dependence in their widths. The differences in line width and the presence of forbidden transitions along the principal axes are attributed to the spread in the crystal field due to the torsional oscillations of the NO-2 groups.

Electron Paramagnetic Resonance ofMn2+in KTaO3

The electron paramagnetic resonance of ${\mathrm{Mn}}^{2+}$ in KTa${\mathrm{O}}_{3}$ was measured over a temperature range 4-110 K. At 77 K, the spin-Hamiltonian constants are ${g}_{\ensuremath{\parallel}}=2.000\ifmmode\pm\else\textpm\fi{}0.001$, ${g}_{\ensuremath{\perp}}=2.000\ifmmode\pm\else\textpm\fi{}0.001$, $D=+0.147\ifmmode\pm\else\textpm\fi{}0.003$ ${\mathrm{cm}}^{\ensuremath{-}1}$, ${A}_{\ensuremath{\parallel}}=\ensuremath{-}(86.5\ifmmode\pm\else\textpm\fi{}0.5)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$ ${\mathrm{cm}}^{\ensuremath{-}1}$, ${A}_{\ensuremath{\perp}}=\ensuremath{-}(84\ifmmode\pm\else\textpm\fi{}1.5)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$ ${\mathrm{cm}}^{\ensuremath{-}1}$. The results indicate that the ${\mathrm{Mn}}^{2+}$ is substitutional at a ${\mathrm{Ta}}^{5+}$ site with an adjacent oxygen vacancy. The temperature dependence of $D$ is correlated with the soft-mode frequency of the host. The quadrupole splitting ${Q}^{\ensuremath{'}}=+(0.8\ifmmode\pm\else\textpm\fi{}0.1)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$ ${\mathrm{cm}}^{\ensuremath{-}1}$ was determined from the forbidden hyperfine transitions.

Electron paramagnetic resonance of Mn2+ in zinc acetate dihydrate

Electron paramagnetic resonance of Mn2+ in zinc acetate dihydrate

Fine Structure in Electron Paramagnetic Resonance ofMn2+in Zinc Sulfate

Fine Structure in Electron Paramagnetic Resonance of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msup><mml:mrow><mml:mi mathvariant="normal">Mn</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn><mml:mo>+</mml:mo></mml:mrow></mml:msup></mml:mrow></mml:math>in Zinc Sulfate

Electron paramagnetic resonance of Mn2+B in SrWO4

Electron paramagnetic resonance of Mn2+B in SrWO4