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© 2019 Elsevier Ltd Magnetic properties of a new single crystal MnMgBO 4 have been studied. It was determined that below 16 K antiferromagnet spin order was observed with the axis of easy magnetization along the c axis crystal. The short antiferromagnetic range order was observed below 100 K. The Curie–Weiss temperature has been determined in single crystal MnMgBO 4 as θ CW = −98 K and the frustration parameter has been estimated as 6.125.

© 2019 Elsevier Ltd Microstructural and magnetic properties of potassium aluminoborate glasses 25K2O–25Al2O3–50B2O3 (KAB): 4% Fe2O3(composition in mol %)are studied in a wide temperature range from 4.2 up 690 K by magnetometry, Mössbauer spectroscopy and electron spin resonance (ESR). Two samples of KAB: 4% Fe2O3 before (Sample I)and after annealing (Sample II)at T = 525oC are studied. Based on all obtained experimental data we can conclude that only paramagnetic impurity iron centers were formed in the Sample I, while the additional hematite and ε - Fe2O3 nanoparticles were formed in the Sample II after annealing above the glass transition temperature.

© The Royal Society of Chemistry. Novel heteroleptic Er(iii) and Yb(iii) naphthalocyaninato-phthalocyaninates containing an octa-phenyl or octa-phenoxysubstituted naphthalocyanine deck were synthesised and identified by 1H NMR, EPR and high resolution MALDI-TOF/TOF mass spectrometry. Direct synthesis of novel homoleptic Yb(iii) bis (octa-phenylnaphthalocyaninate) was carried out. Downfield lanthanide induced shifts of the aromatic protons in target compounds were observed compared with the corresponding diamagnetic Lu(iii) complexes. In the near-IR absorption spectra, an increase in ionic radius from Lu(iii) to Er(iii) resulted in a bathochromic shift of the intervalence band up to 1473 nm. This work presents the first experimental EPR study of Yb(iii) bis naphthalocyaninate, where a set of magnetic parameters and properties (including spin, magnitude and sign of magnetic anisotropy parameter D, increased splitting in a crystal field, ferromagnetic f-π interaction etc.) were determined and interpreted by both EPR and SQUID techniques and supported by theoretical considerations.

© 2019 We studied the magnetocaloric effect in a single crystal GdTiO3. Single crystal GdTiO3 had a second order phase transition from a paramagnetic to ferrimagnetic state at 33 K. The maximum entropy change of -ΔS=0.10 J/cm3 K was observed in a 5 T field at the transition temperature. A small anisotropy was found in the magnetization and specific heat in low magnetic fields. The magnetization showed no hysteresis. Temperature dependencies of entropy, which are important for analyzing the refrigeration cycle, were calculated from the magnetization and specific heat measurements. These results indicate that GdTiO3 has the potential for applications as a magnetic refrigerant for hydrogen liquefaction.

© 2019, Allerton Press, Inc. Abstract: The temperature dependences of the magnetic susceptibility in magnetic fields applied parallel and perpendicular to axis с of a Mn0.89Mg1.11BO4 single crystal were measured. Spin ordering typical of an antiferromagnetic with an easy magnetization axis was observed below 16 K. The Dzyaloshinskii–Moriya interaction between spins of manganese ions in Mn0.89Mg1.11BO4 was estimated by analyzing the EPR linewidth.

© 2019, Allerton Press, Inc. Abstract: Single crystals of Cu2AlBO5 and Cu2GaBO5 copper oxyborates are synthesized via solution-melt crystallization and subjected to X-ray diffraction analysis. Parameters of the crystal lattice and the positions of atoms in a unit cell are determined. Copper ions form a structural chain along axis а in Cu2AlBO5 and Cu2GaBO5. Temperature dependences of the magnetic susceptibility are measured. The obtained curves feature kinks at Т = 2.4 (Cu2AlBO5) and 4.1 K (Cu2GaBO5).

© 2018, Springer-Verlag GmbH Austria, part of Springer Nature. X-band EPR spectra on SiCN ceramics, doped with Fe(III) ions, annealed at 800 °C, 1000 °C, 1100 °C, 1285 °C, and 1400 °C have been simulated to understand better their magnetic properties, accompanied by new magnetization measurements in the temperature range of 5–400 K for zero-field cooling (ZFC) and field cooling (FC) at 100C. The EPR spectra reveal the presence of several kinds of Fe-containing nanoparticles with different magnetic properties. The maxima of the temperature variation of ZFC magnetization were exploited to estimate (i) the blocking temperature, which decreased with annealing temperature of the samples and (ii) the distribution of the size of Fe-containing nanoparticles in the various samples, which was found to become more uniform with increasing annealing temperature, implying that more homogenous magnetic SiCN/Fe composites can be fabricated by annealing at even higher temperatures than 1400 °C to be used as sensors. The hysteresis curves showed different behaviors above (superparamagnetic), below (ferromagnetic), and about (butterfly shape) the respective average blocking temperatures, 〈TB〉. An analysis of the coercive field dependence upon temperature reveals that it follows Stoner–Wohlfarth model for the SiCN/Fe samples annealed above 1100 °C, from which the blocking temperatures was also deduced.

© 2016, Pleiades Publishing, Ltd.[FeLX2]Y [L = N,N'-ethylenebis(salicylimine) (salen), N,N'-ethylenebis(acetylacetonylimine) (acen), or N,N'-ethylenebis(3-methyloxysalicylimine) (vanen); X = imidazole or N-methylimidazole; Y = BF4, ClO4, or BPh4] compounds have been prepared and studied by means of EPR and magnetic susceptibility measurements at 5–300 K. It has been shown that the different electron-donating properties of acen and salen planar ligands result in different spin states of Fe(III) ions. Intermolecular π-interactions of the outer-sphere BPh4 ion affect the complexes spin state as well.

© 2016, Pleiades Publishing, Ltd.[FeLX2]Y [L = N,N'-ethylenebis(salicylimine) (salen), N,N'-ethylenebis(acetylacetonylimine) (acen), or N,N'-ethylenebis(3-methyloxysalicylimine) (vanen); X = imidazole or N-methylimidazole; Y = BF4, ClO4, or BPh4] compounds have been prepared and studied by means of EPR and magnetic susceptibility measurements at 5–300 K. It has been shown that the different electron-donating properties of acen and salen planar ligands result in different spin states of Fe(III) ions. Intermolecular π-interactions of the outer-sphere BPh4 ion affect the complexes spin state as well.

© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim New nickel-based complexes of 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene (dpp-bian) with BF4− counterion or halide co-ligands were synthesized in THF and MeCN. The nickel(I) complexes were obtained by using two approaches: 1) electrochemical reduction of the corresponding nickel(II) precursors; and 2) a chemical comproportionation reaction. The structural features and redox properties of these complexes were investigated by using single-crystal X-ray diffraction (XRD), cyclic voltammetry (CV), and electron paramagnetic resonance (EPR) and UV/Vis spectroscopy. The influence of temperature and solvent on the structure of the nickel(I) complexes was studied in detail, and an uncommon reversible solvent-induced monomer/dimer transformation was observed. In the case of the fluoride complex, the unpaired electron was found to be localized on the dpp-bian ligand, whereas all of the other nickel complexes contained neutral dpp-bian moieties.

© 2019, Pleiades Publishing, Ltd. Abstract: FePt thin films are made via the heat treatment of structures containing Pt (001) and Fe (001) epitaxial layers. X-ray spectral analysis and field-emission scanning electron microscopy show that the samples contain the cubic L12–Fe3Pt phase and the tetragonal L10–FePt phase. The magnetic anisotropy of the thin films is studied by ferromagnetic resonance and magnetometric methods. The contributions from the cubic and tetragonal phases to the ferromagnetic-resonance spectrum of the sample are distinguished. The key characteristics of thin films which determine their practical applicability are determined: the Gilbert damping parameter G ~ 0.4, the first and second crystal anisotropy constants K1⊥ = –4.08 × 106 erg/cm3, K2⊥ = 1.34 × 106 erg/cm3, K2|| = –9.76 × 104 erg/cm3.

© the Partner Organisations. The authors regret that there is an error within the Acknowledgments section of the article. The sentence "This research was made possible by an RNF 14-23-00016 grant" is incorrect. The correct version of this sentence is shown below. This work was supported by the Russian Science Foundation (grant no. 14-23-00016). The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers.

Copyright © 2019 American Chemical Society. The unusual temperature behavior of the electron spin resonance (ESR) spectra and magnetic properties are experimentally observed in copper(II) complexes with a dendritic ligand based on the Boltorn H30 polymer (Perstorp Specialty Chemicals AB, Sweden) functionalized with fumaric acid residues in a molar ratio of 1:6. The ESR spectra at low temperatures show signs of transition to higher spin states at temperatures below 8-10 K, and the temperature dependences of the integral ESR signal intensities and magnetic susceptibility show the positive deviation from the Curie-Weiss law, thereby pointing to the presence of ferromagnetic exchange interactions in the system under study. The values of the exchange interaction parameters are calculated by quantum-chemical simulation of the possible structure of the copper(II) complex when assuming the formation of trinuclear coordination sites embedded in the hyperbranched polymer structure. The results of density functional theory calculations indicate the possibility of ferromagnetic exchange through carboxylate bridges in the trinuclear magnetic clusters, and the calculated values of the exchange interaction parameters make it possible to construct theoretical curves of the temperature dependence of the effective magnetic moment, which satisfactorily fit the experimental data, especially considering that polymers are characterized by disperse molecular weights and chemical structures.

© 2019 The Royal Society of Chemistry. Binary nanoparticles, composed of two different metals, attract significant attention because they possess properties not typical for their respective single-component nanoparticles. In the bulk form, iron and nickel form an alloy called invar in which the two metals are mixed in a ratio of Fe:Ni = 2:1. In this work, we demonstrate the formation of alloyed nanoparticles of invar, as opposed to the theoretically possible formation of particles from the two individual metals. The formation of the alloyed nanoparticles is conducted in a two-step process: liquid phase impregnation of graphene oxide with the salts of the metals, and subsequent annealing of the as-formed dry composite. Unlike the solution phase reaction conditions, in this approach, the binary nanoparticles are assembled under conditions where the metal atoms are immobilized on the surface of the decomposing graphene oxide, and at temperatures significantly lower than the melting points of the two metals. The structure of the as-grown nanocrystals is investigated by Mössbauer spectroscopy, powder X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscopy. The majority of the Fe/Ni nanoparticles are in a magnetically ordered state, and the composite is a soft magnet.

© 2019 Trans Tech Publications, Switzerland. 0.85La0.7 Sr0.3 MnO3 /0.15GeO2 composite material and pure La0.7 Sr0.3 MnO3 were investigated by X-ray diffraction, scanning electron microscopy, magnetometry and electron spin resonance methods. It was observed that both samples demonstrate the ferromagnetic properties, while the absolute value of the magnetization, the magnetic entropy change and the magnetic ordering temperature decrease in composite in comparison with pure La0.7 Sr0.3 MnO3 . The electron spin resonance spectra of investigated (1-x)La0.7 Sr0.3 MnO3 /xGeO2 (x=0, 0.15) can be attributed to the superposition of electron spin resonance spectra from magnetically anisotropic particles with different orientations.

© 2018 Elsevier B.V. Electron paramagnetic resonance (EPR) study of the impurity Gd3+ ions in the multi-site SrY2O4 crystal isostructural to the magnetically-frustrated SrGd2O4 compound is reported. Analysis of the angular dependences of the EPR spectra at room temperature allowed us to establish the spin-level energy patterns in the ground states of the Gd3+ ions at the Y(1) and Y(2) sites. Parameters of the spin-Hamiltonian in the frames related to the crystal axes and to the principal center axes are determined.

© 2019 Elsevier B.V. We have implanted ZnO thin film with 40 keV Fe+ ions to a high fluence of 1.25 × 1017 ions/cm2. Elemental and magnetic phase compositions were investigated by XRD, XPS, CEMS, and VSM methods. The Fe-implanted ZnO film reveals strong ferromagnetism at room temperature. The implanted iron ions are found in different valence states of Fe2+ and Fe3+. It was attributed to the formation of paramagnetic and ferromagnetic iron-based phases. The ferromagnetism is explained with the formation of a magnetic ordered solution of iron ions in ZnO matrix. Post-implantation annealing in a high vacuum results in the decrease of magnetism due to the formation of magnetite nanoparticles.

© 2019 Elsevier Ltd and Techna Group S.r.l. The structural and magnetic properties of YbMnO 3 and Yb 0.82 Sr 0.18 MnO 3 multiferroics were studied by neutron powder diffraction (NPD), magnetometry and electron spin resonance (ESR) technics in a wide temperature range. Neutron diffraction measurements showed that the substitution of ytterbium ions with strontium ions in hexagonal h - YbMnO 3 (space group P6 3 cm) leads to the destabilization of the crystal structure of the last compound and appearance of the mixture of three phases with different structure: hexagonal phase h - Yb 0.95 Sr 0.05 MnO 3 (space group P6 3 cm), orthorhombic phase o - Yb 0.69 Sr 0.31 MnO 3 (space group Pbnm), hexagonal phase SrMnO 3 (space group P6 3 cm). This fact was proved by the ESR measurements in which a several signals due to the phases of different structure were observed. NPD measurements showed that the magnetic structure of h - Yb 0.95 Sr 0.05 MnO 3 phase is similar to the magnetic structure of the pure h - YbMnO 3 and demonstrate the presence of the antiferromagnetic ordering in the samples. ESR and magnetization measurements of h - YbMnO 3 sample proved the presence of the antiferromagnetic correlations and also they showed the appearance of the ferromagnetically correlated nanoregions.

© 2018 Elsevier Ltd In this study, we synthesized single crystals of NaxCoO2 with x ∼0.8 using the optical floating zone technique. A thorough electrochemical treatment of the samples permitted us to control the de-intercalation of Na to obtain single crystal samples of stable Na ordered phases with x = 0.5–0.8. Comparisons of the bulk magnetic properties with those observed in the Na ordered powder samples confirmed the high quality of these single crystal phases. The ab plane resistivity was measured for the Na ordered samples and it was quite reproducible for different sample batches. The data were analogous to those found in previous initial experimental studies on single crystals, but the lower residual resistivity and sharper anti-ferromagnetic transitions determined for our samples confirmed their higher quality.

© Kazan Federal University (KFU).[Fe(3-MeO-Qsal)2]Y (Y = PF6, BF4, NCS, NO3, BPh4) compounds were synthesized using the diffusion method and studied by the electron spin resonance and the magnetic susceptibility methods in the temperature range (5-300) K. Coexistence of spatially separated high-spin and low-spin fractions in these compounds was observed. Low-spin fraction of all compounds reveals the antiferromagnetic correlations at low temperatures. High-spin fraction of complexes with Y = PF6 demonstrate the weak ferromagnetic properties due to exchange interaction between complexes in whole temperature range. Influence of outer-sphere anion on the spin state, the electronic properties of low-spin Fe(III) complexes is demonstrated.

© Published under licence by IOP Publishing Ltd.We present the results of magnetic and Mössbauer effect studies of zinc oxide thin film obtained by RF magnetron sputtering and implanted with 40 keV iron ions to a fluence of 1.5•1017 ion/cm2. As-implanted and post-annealed sample shows ferromagnetic properties at room temperature and consists of paramagnetic and ferromagnetic phases according to Mössbauer spectroscopy.

© 2016 Elsevier B.V.Here we report the magnetic susceptibility measurements of magnetron sputtered orthorhombic manganite RMnO3 (R=Yb, Gd) thin films deposited on dielectric LaAlO3 and ferroelectric SrTiO3, LiNbO3 substrates. We observed that all of investigated o-RMnO3 films show a splitting in the temperature dependence of ZFC and FC magnetization curves. We found that the substrate can impact on the splitting temperature ZFC-FC curves and absolute value of the magnetization of thin films.

© 2016, Pleiades Publishing, Inc.New composite materials (SrFe12O19)x(CaCu3Ti4O12)1–x (x = 0, 0.05, 1) have been synthesized. Their magnetic properties are studied in the temperature range 5–300 K using the magnetic resonance and magnetometry methods. It is found that strontium hexaferrite microinclusions in the (SrFe12O19)0.05(CaCu3Ti4O12)0.95 composite “magnetize” CaCu3Ti4O12 at temperatures from 300 to 200 K, forming a ferrimagnetic particle near the SrFe12O19 “core.” The magnetic resonance line below 200 K splits into two lines corresponding to SrFe12O19 and CaCu3Ti4O12. The core effect decoration is manifested in the increase in the Curie–Weiss temperature from 25 K in CaCu3Ti4O12 without the doping ceramics to 80 K in the composite with 5% of SrFe12O19.

© 2016 Elsevier B.V.Here we report the magnetic susceptibility measurements of magnetron sputtered orthorhombic manganite RMnO3 (R=Yb, Gd) thin films deposited on dielectric LaAlO3 and ferroelectric SrTiO3, LiNbO3 substrates. We observed that all of investigated o-RMnO3 films show a splitting in the temperature dependence of ZFC and FC magnetization curves. We found that the substrate can impact on the splitting temperature ZFC-FC curves and absolute value of the magnetization of thin films.

© 2015 American Physical Society. SrEr2O4 is a geometrically frustrated magnet which demonstrates rather unusual properties at low temperatures including a coexistence of long- and short-range magnetic order, characterized by two different propagation vectors. In the present work, the effects of crystal fields (CFs) in this compound containing four magnetically inequivalent erbium sublattices are investigated experimentally and theoretically. We combine the measurements of the CF levels of the Er3+ ions made on a powder sample of SrEr2O4 using neutron spectroscopy with site-selective optical and electron paramagnetic resonance measurements performed on single-crystal samples of the lightly Er-doped nonmagnetic analog, SrY2O4. Two sets of CF parameters corresponding to the Er3+ ions at the crystallographically inequivalent lattice sites are derived which fit all the available experimental data well, including the magnetization and dc susceptibility data for both lightly doped and concentrated samples.

Single crystals of sodium cobaltates NaxCoO2 with x ≈ 0.8 were grown by the floating zone technique. Using electrochemical Na de-intercalation method we reduced the sodium content in the as-grown crystals down to pure phase with 22 K Néel temperature and x ≈ 0.77. The 59Co NMR study in the paramagnetic state of the TN = 22 K phase permitted us to evidence that at least 6 Co sites are differentiated. They could be separated by their magnetic behavior into three types: a single site with cobalt close to non-magnetic Co3+, two sites with the most magnetic cobalts in the system, and the remaining three sites displaying an intermediate behavior. This unusual magnetic differentiation calls for more detailed NMR experiments on our well characterized samples. © 2014 Pleiades Publishing, Inc.

© 2017 O. I. Medvedeva et al. A series of cobalt (Co) and its oxides based nanoparticles were synthesized by using hyperbranched polyester polyol Boltorn H20 as a platform and sodium borohydride as a reducing agent. UV, FT-IR, XRD, NTA, and TEM methods were employed to obtain physicochemical characteristics of the products. The average diameter of Co nanoparticles was approximately 8.2±3.4 nm. Their magnetic properties, including hysteresis loop, field-cooled, and zero field-cooled curves were investigated. The nanoparticles exhibit superparamagnetism at room temperature, accompanied by magnetic hysteresis below the blocking temperature.

© 2017 Elsevier B.V. (SrFe 12 O 19 ) x (CaCu 3 Ti 4 O 12 ) 1-x (x = 0.01, 0.03, 0.07, 0.1) composites were synthesized using a solid state method, while the pre-synthesized strontium hexaferrite SrFe 12 O 19 (SFO) was added to the stoichiometric amount of CaO, CuO and TiO oxides to form the CaCu 3 Ti 4 O 12 (CCTO) structure around SFO microinclusions. The structural and microstructural properties of obtained composites were studied by X-ray diffraction, scanning electron microscopy and transmission electron microscopy techniques. The magnetic properties were studied by electron spin resonance and magnetometry methods. Based on all experimental data we can conclude, that SFO x CCTO 1-x nanostructured composites were formed only for concentrations x = 0.03 and x = 0.07, where SFO nanoinclusions are inside CCTO matrix, that leads to the strong mutual influence of the magnetic properties of both component.

© 2016 Published under licence by IOP Publishing Ltd. Here we present the investigation of the orthorhombic o-LuFeO 3 thin film grown on SrTiO 3 (001) substrate. Temperature dependencies of magnetization measured in magnetic fields 1000 Oe and 2000 Oe were described in the assumption that ferromagnetic correlated regions are presented in samples together with the paramagnetic phase. Additional argument in favor of the ferromagnetic regions existence in o-LuFeO 3 is the magnetic hysteresis curve measured at T=5 and 100K. The temperature dependences of dielectric response were measured and analyzed.

© 2017 Elsevier B.V. (La 0.7 Sr 0.3 MnO 3 ) x (CaCu 3 Ti 4 O 12 ) 1−x (0.01 ≤ x ≤ 0.3) nanostructured composites with La 0.7 Sr 0.3 MnO 3 (LSMO) microinclusions in CaCu 3 Ti 4 O 12 (CCTO) matrix were synthesized using a solid state method. The structural and microstructural details were studied by X-ray diffraction (XRD), X-ray fluorescence (XFA), scaning electron microscope (SEM) and transmission electron microscope (TEM) techniques. The magnetic properties were studied by electron spin resonance (ESR) and magnetometry methods. In the concentration range 0.01 < x < 0.1 physical properties of composites differ from the properties of the individual components CCTO or LSMO. The Curie temperature of the ferromagnetic phase for all concentrations is T C = 315 K, that is less at 50 K than in pure LSMO. The Weiss constant of the paramagnetic phase has the strong concentration dependance. The observed mutual influence on the magnetic properties of both components can be tentatively attributed to the interface exchange interactions between them, hinting a possible magnetic proximity effect.

© 2017 Elsevier B.V. (La 0.7 Sr 0.3 MnO 3 ) x (CaCu 3 Ti 4 O 12 ) 1−x (0.01 ≤ x ≤ 0.3) nanostructured composites with La 0.7 Sr 0.3 MnO 3 (LSMO) microinclusions in CaCu 3 Ti 4 O 12 (CCTO) matrix were synthesized using a solid state method. The structural and microstructural details were studied by X-ray diffraction (XRD), X-ray fluorescence (XFA), scaning electron microscope (SEM) and transmission electron microscope (TEM) techniques. The magnetic properties were studied by electron spin resonance (ESR) and magnetometry methods. In the concentration range 0.01 < x < 0.1 physical properties of composites differ from the properties of the individual components CCTO or LSMO. The Curie temperature of the ferromagnetic phase for all concentrations is T C = 315 K, that is less at 50 K than in pure LSMO. The Weiss constant of the paramagnetic phase has the strong concentration dependance. The observed mutual influence on the magnetic properties of both components can be tentatively attributed to the interface exchange interactions between them, hinting a possible magnetic proximity effect.

© 2017 Elsevier B.V. (SrFe 12 O 19 ) x (CaCu 3 Ti 4 O 12 ) 1-x (x = 0.01, 0.03, 0.07, 0.1) composites were synthesized using a solid state method, while the pre-synthesized strontium hexaferrite SrFe 12 O 19 (SFO) was added to the stoichiometric amount of CaO, CuO and TiO oxides to form the CaCu 3 Ti 4 O 12 (CCTO) structure around SFO microinclusions. The structural and microstructural properties of obtained composites were studied by X-ray diffraction, scanning electron microscopy and transmission electron microscopy techniques. The magnetic properties were studied by electron spin resonance and magnetometry methods. Based on all experimental data we can conclude, that SFO x CCTO 1-x nanostructured composites were formed only for concentrations x = 0.03 and x = 0.07, where SFO nanoinclusions are inside CCTO matrix, that leads to the strong mutual influence of the magnetic properties of both component.

© Published under licence by IOP Publishing Ltd.We present the results of magnetic and Mössbauer effect studies of zinc oxide thin film obtained by RF magnetron sputtering and implanted with 40 keV iron ions to a fluence of 1.5•1017 ion/cm2. As-implanted and post-annealed sample shows ferromagnetic properties at room temperature and consists of paramagnetic and ferromagnetic phases according to Mössbauer spectroscopy.

© 2016 Elsevier B.V.Here we report the magnetic susceptibility measurements of magnetron sputtered orthorhombic manganite RMnO3 (R=Yb, Gd) thin films deposited on dielectric LaAlO3 and ferroelectric SrTiO3, LiNbO3 substrates. We observed that all of investigated o-RMnO3 films show a splitting in the temperature dependence of ZFC and FC magnetization curves. We found that the substrate can impact on the splitting temperature ZFC-FC curves and absolute value of the magnetization of thin films.

© 2016 Elsevier B.V.Here we report the magnetic susceptibility measurements of magnetron sputtered orthorhombic manganite RMnO3 (R=Yb, Gd) thin films deposited on dielectric LaAlO3 and ferroelectric SrTiO3, LiNbO3 substrates. We observed that all of investigated o-RMnO3 films show a splitting in the temperature dependence of ZFC and FC magnetization curves. We found that the substrate can impact on the splitting temperature ZFC-FC curves and absolute value of the magnetization of thin films.

© Kazan Federal University (KFU).[Fe(3-MeO-Qsal)2]Y (Y = PF6, BF4, NCS, NO3, BPh4) compounds were synthesized using the diffusion method and studied by the electron spin resonance and the magnetic susceptibility methods in the temperature range (5-300) K. Coexistence of spatially separated high-spin and low-spin fractions in these compounds was observed. Low-spin fraction of all compounds reveals the antiferromagnetic correlations at low temperatures. High-spin fraction of complexes with Y = PF6 demonstrate the weak ferromagnetic properties due to exchange interaction between complexes in whole temperature range. Influence of outer-sphere anion on the spin state, the electronic properties of low-spin Fe(III) complexes is demonstrated.

© 2016, Pleiades Publishing, Inc.New composite materials (SrFe12O19)x(CaCu3Ti4O12)1–x (x = 0, 0.05, 1) have been synthesized. Their magnetic properties are studied in the temperature range 5–300 K using the magnetic resonance and magnetometry methods. It is found that strontium hexaferrite microinclusions in the (SrFe12O19)0.05(CaCu3Ti4O12)0.95 composite “magnetize” CaCu3Ti4O12 at temperatures from 300 to 200 K, forming a ferrimagnetic particle near the SrFe12O19 “core.” The magnetic resonance line below 200 K splits into two lines corresponding to SrFe12O19 and CaCu3Ti4O12. The core effect decoration is manifested in the increase in the Curie–Weiss temperature from 25 K in CaCu3Ti4O12 without the doping ceramics to 80 K in the composite with 5% of SrFe12O19.

© 2015 American Physical Society. SrEr2O4 is a geometrically frustrated magnet which demonstrates rather unusual properties at low temperatures including a coexistence of long- and short-range magnetic order, characterized by two different propagation vectors. In the present work, the effects of crystal fields (CFs) in this compound containing four magnetically inequivalent erbium sublattices are investigated experimentally and theoretically. We combine the measurements of the CF levels of the Er3+ ions made on a powder sample of SrEr2O4 using neutron spectroscopy with site-selective optical and electron paramagnetic resonance measurements performed on single-crystal samples of the lightly Er-doped nonmagnetic analog, SrY2O4. Two sets of CF parameters corresponding to the Er3+ ions at the crystallographically inequivalent lattice sites are derived which fit all the available experimental data well, including the magnetization and dc susceptibility data for both lightly doped and concentrated samples.

Single crystals of sodium cobaltates NaxCoO2 with x ≈ 0.8 were grown by the floating zone technique. Using electrochemical Na de-intercalation method we reduced the sodium content in the as-grown crystals down to pure phase with 22 K Néel temperature and x ≈ 0.77. The 59Co NMR study in the paramagnetic state of the TN = 22 K phase permitted us to evidence that at least 6 Co sites are differentiated. They could be separated by their magnetic behavior into three types: a single site with cobalt close to non-magnetic Co3+, two sites with the most magnetic cobalts in the system, and the remaining three sites displaying an intermediate behavior. This unusual magnetic differentiation calls for more detailed NMR experiments on our well characterized samples. © 2014 Pleiades Publishing, Inc.