The problem of determining the magnitude of the atomic magnetic moments in compounds with rare-earth and transition elements using the X-ray magnetic circular dichroism (XMCD) is investigated. The ...standard sum rules approach usually gives the moment values by several times smaller than their bulk values obtained from the direct magnetic measurements. We attribute this to the strong spin fluctuations in the surface layer which actually formed the soft XMCD signal. A method of determining the value of the local magnetic moments in the presence of strong fluctuations is proposed. The magnetic interactions in La0.5Pr0.2Ca0.3MnO3 are investigated by x-ray absorption spectroscopy, XMCD and bulk magnetization measurements. The proposed procedure is used to determine the values of atomic magnetic moments of transition and rare-earth elements as well as net magnetization on the surface and in the bulk from experimental Mn L2,3 and Pr M4,5 XMCD spectra.
•Strong spin fluctuations at the surface (TEY depth 10nm) reduce the XMCD spectra.•The Mn L2;3 XMCD decomposition show two signals from up and down magnetic moments.•The sum rules give the Mn and Pr magnetization at the surface and in the bulk.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The magnetic, transport, optical, and elastic properties of the electron-doped manganites CaMn1-xMxO3 with Mn-site doping (M=Mo or W, x≤0.20) are studied and the results are compared with those of ...Ca-site substituted manganites with the same Mn3+ concentration. If Mn3+ concentration is lees than 10%, the charge carriers' localization due to lattice distortions in the Ca-site doped samples is stronger than the localization caused by magnetic dilution in the case of Mn-site substitution. At higher Mn3+ concentration, the magnetic dilution plays a key role.
Influence of the substitution of Hg by Cd on Kerr effect, magnetoreflection, and magnetotransmission of unpolarized light for Hg1-xCdxCr2Se4 (0≤x≤1) single-crystals is studied. The changes in the ...magnetooptical properties of the ferromagnetic spinels are shown to occur in compositions with x>0.1. The giant values of magnetooptical effects in Hg1-xCdxCr2Se4 spinels can be used in the magnetooptoelectronics.
Glasses of the K2O–B2O3–GeO2 system were studied by means of Raman and IR spectroscopy. The density of the samples was measured and the dependence of the molar volume and atomic density on ...composition was calculated. Curve-fitting of Raman spectra was applied to obtain a definition of the main structural units formed in the system. The conditions for highly-coordinated boron and germanium atoms were obtained. It was shown that potassium cations remain connected to germanate structural units at a B/Ge ratio of up to 1, whereas the explicit redistribution of borate and germanate structural groupings becomes most noticeable only at a B/Ge ratio > 2.
Glasses of the K
O-B
O
-GeO
system were studied by means of Raman and IR spectroscopy. The density of the samples was measured and the dependence of the molar volume and atomic density on composition ...was calculated. Curve-fitting of Raman spectra was applied to obtain a definition of the main structural units formed in the system. The conditions for highly-coordinated boron and germanium atoms were obtained. It was shown that potassium cations remain connected to germanate structural units at a B/Ge ratio of up to 1, whereas the explicit redistribution of borate and germanate structural groupings becomes most noticeable only at a B/Ge ratio > 2.
Glasses of the K
2
O-B
2
O
3
-GeO
2
system were studied by means of Raman and IR spectroscopy. The density of the samples was measured and the dependence of the molar volume and atomic density on ...composition was calculated. Curve-fitting of Raman spectra was applied to obtain a definition of the main structural units formed in the system. The conditions for highly-coordinated boron and germanium atoms were obtained. It was shown that potassium cations remain connected to germanate structural units at a B/Ge ratio of up to 1, whereas the explicit redistribution of borate and germanate structural groupings becomes most noticeable only at a B/Ge ratio > 2.
Glasses of the K
2
O-B
2
O
3
-GeO
2
system were studied by means of Raman and IR spectroscopy.
The Raman spectra of x%Cs2O-(100 − x)%SiO2 (x=17, 22, 27, 33, and 37 mol%) glasses and melts were measured in the temperature range of 293 to 1553 K. The concentrations of the Qn species were ...calculated as a function of the composition and temperature based on the deconvolution analysis of the spectra. It was found that a dynamic equilibrium among structural units in the melts with x>17 mol% can be described by disproportionation reaction Q3⇔Q4+Q2. The enthalpy of this reaction was found to be equal to 32 ± 6, 43 ± 8, 56 ± 10, and 52 ± 9 for x=22, 27, 33, and 37 mol%, respectively. The nonideal entropy of mixing (ΔSmix) depends on the melt temperature and increases almost linearly with increasing temperature. The Qn, Q2–Q2, and Qn,ijkl distributions with x ranging from 0 to 55 mol% were modeled using experimental data for the concentrations of the Qn units.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
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