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The synthesis, structures, adsorption, and magnetic properties of two two-dimensional (2D) coordination polymers, [M(btca)1/2(bpe)1/2(H2O)2]n (M = Ni2+ (1) and Co2+ (2); H4btca = 1,2,4,5-benzenetetracarboxylic acid; bpe = 1,2-di(4-pyridyl)ethane) constructed by mixed bipyridyl–tetracarboxylate ligands were reported. Single-crystal X-ray diffraction studies reveal the 3D hydrogen-bonded networks sustained by O–H⋯O H bonds between the 2D layers. The 2D structure topology of the compounds is a new {4.6·2}2{4·2.6·2.8·2} bex topology while the 3D framework is different because of the distinct H bond interactions. Both compounds exhibit high thermal stability above 150 °C. N2 adsorption measurements reveal that both compounds are non-porous structures, while compound 1 exhibits CO2 adsorption, possibly due to structural expansion after CO2 accommodation. Magnetic investigations indicated that framework 2 exhibits field-induced slow magnetic relaxation due to the large magnetic anisotropy of Co2+ ions (zero-field splitting parameter D = 42.1 cm−1), while framework 1 shows simple paramagnetism with a small D of −11.3 cm−1. This work not only provides two new coordination polymers but also a potential bipyridyl–tetracarboxylate approach for the design and construction of single-ion magnet (SIM) frameworks. [ABSTRACT FROM AUTHOR]

Using the example of the mineral magnetite, which is the main component of magnetic volcanic sand, a quantum-chemical analysis of the nature of paramagnetic properties was carried out using the molecular orbital method. Magnetic properties are among the most important characteristics of substances, and magnetic interaction is one of the fundamental forces in the universe. Understanding the chemical nature of magnetic properties allows not only to effectively use materials with magnetic properties, but also to create new materials with the desired characteristics. The magnetic properties of substances depend on their structure and elemental composition, since each charged particle inside the substance has its own magnetic moment-spin. [ABSTRACT FROM AUTHOR]

The electron paramagnetic resonance (EPR) spectrum of nitrogen implanted SnO2 thin films have been study. An isotropic g (gyromagnetic ratio) tensor is observed and calculated for all Samples (viz. as deposited and for different concentration of nitrogen in SnO2). The different g values are attributed to the different concentration of paramagnetic species. With the increase in doping of nitrogen from 2% to 6%, the substitution of oxygen vacancies and interstitial atom in electronic structure is also observed. This is confirmed by absorption spectrum recorded by UV Visible. [ABSTRACT FROM AUTHOR]

The direct two‐step synthesis of new coordination polymer [Co2(pyz)(tfa)2(dmf)6(H2O)][Co3(μ3‐F)(tfa)6(pyz)(dmf)]2 ⋅ 2dmf, (where pyz=pyrazine, Htfa=trifluoroacetic acid, dmf=dimethyl formamide) containing the fluoro‐centered secondary building block [Co3(μ3‐F)(tfa)6], is reported. The substance characterization using single‐crystal XRD, powder XRD, IR‐spectroscopy and thermogravimetry was performed. SCXRD data revealed the presence of cationic and anionic subsystems, both containing cobalt(II) ions and pyrazine bridging ligands. The magnetic proper‐ties of the compound were collected and discussed. Temperature dependence of magnetic susceptibility shows Curie–Weiss like behavior at all studied temperatures. [ABSTRACT FROM AUTHOR]

In contrast to the observed high-temperature superconductivity in monolayer FeSe / SrTiO 3 films, akin to CoS b / SrTiO 3 , the bulk counterpart, FeSe, does not exhibit superconductivity even under elevated pressure, and its magnetic characteristics remain subject to debate. This investigation delves into the electrical and magnetic attributes, alongside X-ray photoelectron spectroscopy (XPS) analysis, of FeSe mono-crystal. Magnetic and electrical transport assessments indicate that FeSe demonstrates characteristics of a Pauli paramagnetic metal within non-Fermi liquid traits. XPS analysis further reveals that the Fe and Se pair in FeSe exist in a zero-valence state, forming a predominantly metallic-bonded alloy. The Pauli paramagnetism observed in FeSe is ascribed to its itinerant electrons. The comprehension of the electronic states in FeSe mono-crystal not only clarifies its lack of magnetic characteristics but also paves the way for exploring potential high-temperature superconductivity. [ABSTRACT FROM AUTHOR]

Following chemical intuition, one would expect that all closed‐shell molecules are diamagnetic. However, it is known that this is not the case for some second‐row hydrides with low‐lying unoccupied π orbitals due to an unquenching of the total angular momentum in the presence of an external magnetic field. In this article, the transition‐metal hydrides ScH and YH are investigated, assuming a similar unquenching effect involving low‐lying unoccupied π and δ orbitals formed from the metal d orbitals rather than the p orbitals. We are comparing results obtained with various quantum‐chemical methods (HF, CCSD, CCSD(T), CCSDT) and basis sets. The obtained positive values for the magnetizabilities clearly indicate paramagnetic behavior. Vibrational effects on the magnetizability tensor are also considered, but these effects are small and do not change the overall conclusion that both ScH and YH are further examples for closed‐shell paramagnetism. [ABSTRACT FROM AUTHOR]

The spin degree of freedom of charge carriers in halide‐perovskite semiconductors can be highly useful for information photonics applications. The Faraday effect is known to be the best indicator of paramagnetism of the material and of the spin‐light interaction. In this work, the Faraday effect is demonstrated, for the first time, in a hybrid organic–inorganic halide perovskite MAPbI3 (MA+ = CH3NH3+$_3^+$). The Faraday rotation and birefringence are measured across the tetragonal‐cubic phase transition at 327 K. The Faraday rotation is strongly suppressed below the phase transition temperature due to anisotropy (linear birefringence) of the tetragonal crystal phase. The situation changes drastically above the phase transition temperature, when the crystal becomes optically isotropic. The emerging Faraday rotation obeys the Curie law, demonstrating its population‐related paramagnetic nature. This observation opens new prospects for application of these systems and for their investigations using methods of the polarization noise spectroscopy applicable to optically anisotropic materials. [ABSTRACT FROM AUTHOR]

Herein, the synthesis of Co2Si5N8 nitridosilicate from α‐Ca2Si5N8 by ion exchange is described. The monoclinic Co2Si5N8$\left(\text{Co}\right)_{2} \left(\text{Si}\right)_{5} \left(\text{N}\right)_{8}$ structure (space group Cc) is compared with those of the related nitridosilicates Ca2Si5N8 and Fe2Si5N8 its magnetic properties are profoundly investigated. Most interestingly, polycrystalline Co2Si5N8 exhibits a quasi‐temperature‐independent paramagnetic susceptibility of about 6×10−3 cm3 mol−1$>$$ 6\times {10}^{-3} {\text{cm}}^{3} {\text{mol}}^{-1}$$ over a wide temperature range from 100 to 600 K. Two different magnetic models based on a phenomenological Hamiltonian that takes into account magnetic exchange coupling, crystal‐field interactions, and Zeeman effects within the framework of an angular momentum basis set are refined to the experimental susceptibility datasets. The results of the refinements point to the realization of a pseudo temperature independent paramagnetism for Co2Si5N8 that results from a near‐perfect cancellation of temperature‐dependent contributions to the susceptibility depending delicately on the mixing of ion levels in the electronic states, their relative energies, and the magnetic coupling between them. Additionally, performed direct current field scan, alternating current susceptibility, and heat capacity measurements complete the magnetic characterization and facilitate the identification of impurity phase contributions. [ABSTRACT FROM AUTHOR]

The reaction of [(dpp-bian)Yb(DME)2] with one equivalent of dpp-bian and one equivalent of potassium or sodium gave the ate complexes [(dpp-bian)2Yb][K(DME)4] and [(dpp-bian)2Yb][Na(THF)6]. The reaction of [(dpp-bian)YbI(DME)]2 with potassium cyclopentadienide (CpK) led to the complex [{(dpp-bian)CpYb(μ-Cp)· K(Et2O)2}2(μ-Cp)2Yb(THF)2]. In all three compounds, the redox-active dpp-bian exhibits a dianionic state. Yb3+ cations in the prepared compounds determine their paramagnetism. Despite this, resolved 1H and 13C NMR spectra were obtained for [(dpp-bian)2Yb][K(DME)4] and [(dpp-bian)2Yb][Na(THF)6] in THF-d8, which made it possible to assign observed signals. The new compounds were characterized by IR and NMR spectroscopy and elemental analysis (C, H, N). The molecular structure of the prepared complexes was determined by X-ray diffraction [ABSTRACT FROM AUTHOR]

This research paper delves into the synthesis and characterization of Mn-doped nitrogen-co-doped CdS composite diluted magnetic semiconductor quantum dots (DMSQDs) using a co-precipitation method (CPM) at room temperature. The introduction of nitrogen is strategically employed to improve the structural stability of DMSQDs, capitalizing on it's ability to exist in diverse ionic states. The investigation covers the structural, optical, and magnetic properties of the synthesized quantum dots. X-ray diffraction (XRD) analysis confirms the cubic phase of CdS and unveils the presence of secondary phases, including MnS and S2N4, signifying successful Mn and N incorporation into the CdS lattice. Elemental analysis via energy-dispersive X-ray spectroscopy (EDX) validates the presence of Mn and N in the quantum dots. Optical studies, encompassing Ultraviolet-Visible spectra (UV-Vis) and photoluminescence (PL), reveal a distinctive blue shift in the absorption band edge, highlighting the quantum confinement effect. The PL spectra unveil the presence of manganese ions and showcase a characteristic emission peak at 634 nm. Electron paramagnetic resonance (EPR) analysis establishes the paramagnetic nature of Mn-doped CdS composite quantum dots, with nitrogen influencing the g value. This study offers valuable insights into the potential applications of these DMSQDs in the realm of spintronic devices. [ABSTRACT FROM AUTHOR]

Dielectric constants determine the level of miniaturization in capacitive components involved in electronic devices. Cu‐Li co‐doping is attempted to introduce the multiferroic relaxor nature of dielectricity and dilute magnetism in the bulk material simultaneously as Li+ ion substitution in ZnO lattice is known to form acceptor states within the band gap of ZnO and paramagnetic Cu2+ present in ZnO lattice can introduce dilute magnetism. Phase purity and substitution of Cu2+ and Li+ ions in ZnO lattice along with oxide‐ion vacancy formation was confirmed using Powder x‐ray diffraction (XRD), Scanning Electron Microscope (SEM), and Energy Dispersive X‐ray analysis (EDX), X‐ray Photoelectron Spectroscopy (XPS), Inductively Coupled Plasma Mass Spectrometry (ICP‐MS) and Magnetic property measurement system (MPMS) studies. The dielectric constant (ϵr′) of bulk pristine Zn0.92Cu0.05Li0.03O and Zn0.9Cu0.05Li0.05O is found to be 18000 and 20000 respectively at 1000 Hz frequency at 600 °C. Both dielectric constant and dielectric loss were decreasing with increasing frequencies. The increase in dielectric constant (ϵr′) with increasing temperatures at different frequencies for Zn0.92Cu0.05Li0.03O1‐δ and Zn0.9Cu0.05Li0.05O1‐δ is likely due to the localized nature of hopping charge carriers in addition to interfacial polarization due to space charge. Tm was found to increase with increasing frequencies suggesting the relaxor nature of dielectricity in the Zn0.9Cu0.05Li0.05O1‐δ. Bulk pristine Zn0.9Cu0.05Li0.05O1‐δ also exhibits ferroelectricity at room temperature with remnant polarization Pr and Vc equal to 4.20e–02 μC/cm2 and 4.1e+03 V/cm at (30KV, 500 Hz) respectively. Zn0.9Cu0.05Li0.05O also shows the paramagnetic behaviour. [ABSTRACT FROM AUTHOR]

Manganese-co-doped N:CdS composite nanoparticles (CNps) have been prepared by using the co-precipitation method. 2-Mercaptoethonal is used as a surfactant to control the size of nanoparticles. X-ray diffraction (XRD) studies confirm the size of the particles in the nanorange. The Rietveld refinement with X'-pert high-score software studies show multiphase existence in as-prepared composite nanoparticles. The energy dispersive analyses of X-ray studies (EDAX) confirm the presence of doped Mn and nitrogen elements in CdS. The Fourier transform infrared spectroscopy (FTIR) studies confirm the presence of surfactant. The ultraviolet-visible spectroscopy studies (UV-Vis) show a clear blue shift in the band gap, which is an indication of the quantum confinement effect. The photoluminescence studies (PL) attribute the emission of a characteristically strong peak at l = 632 nm, corresponding to the (4T16A1) transition, to the inclusion of Mn2+ in the core of the CdS lattice. The electron paramagnetic spectroscopy (EPR) studies show paramagnetic behavior. The hyperfine splitting constant (A) values around 7 mT from EPR confirms the inclusion of Mn2+ and N3- in the tetrahedral sites of the CdS core. The variation in optical and magnetic properties of as-prepared composite nanoparticles has the potential for optoelectric and magnetoluminescence devices. [ABSTRACT FROM AUTHOR]

Local spin correlation orders emerge in a paramagnetic state, with notable examples such as the partial order, cooperative paramagnetism, and soliton spin liquid. The noncentrosymmetric intermetallic antiferromagnet Mn3RhSi also exhibits the local spin correlation order in the paramagnetic state as magnetic short-range order in a wide temperature range. Here, we show that the local spin correlation order has a spiral structure by neutron scattering measurement of a Mn3RhSi single crystal. The possible origins of the magnetic cluster formation are discussed in terms of the Lifshitz invariant and the Griffiths phase, and compared with the room-temperature skyrmion phase of Co7Zn7Mn6 and non-Fermi liquid behavior of β-Mn. Short-range magnetic orders emerge in a paramagnetic state, with notable examples such as the partial order, cooperative paramagnetism, and soliton spin liquid. Here, the authors use inelastic neutron scattering to investigate short-range magnetic order in Mn3RhSi single crystal finding evidence for a spin spiral cluster, which they suggest may be an origin of the anomalous physical property. [ABSTRACT FROM AUTHOR]

For one of the most famous and widely investigated intermediate-valence compound SmB6, we report the results of a precise experimental study of the pressure effect on magnetic susceptibility χ. The measurements of χ(P) were carried out under helium gas pressure P up to 2 kbar at fixed temperatures 78 and 300 K using a pendulum-type magnetometer. The observed pressure effect value, d lnχ/dP ∼ –6 Mbar–1, demonstrates a noticeable decrease in susceptibility under pressure, which is weakly dependent on temperature used. From model analysis of the experimental data, combined with the supplemented LSDA + U calculations of the electronic structure and van Vleck paramagnetism of the band states of SmB6, we have estimated the value of the initial pressure derivative for the intermediate valence of Sm. It is consistent with the literature data obtained by other methods and indicates an increase in valence with increasing pressure. It was shown that the valence of Sm and its pressure dependence are closely related to the detailed characteristics of the conduction band and 4f states. [ABSTRACT FROM AUTHOR]

Breaking the topological protection of surface states of topological insulators is an essential prerequisite for exploring their applications. This is achievable by magnetic doping, in reduced dimensions, and predictably by introducing disorder beyond a critical level. In certain cases, the former is also known to induce a transition from weak anti-localization (WAL) to weak localization (WL). Here, we report the occurrence of paramagnetism, hopping conduction, and WL in chemically prepared unannealed Dy x Bi 2 − x Se 3 (x = 0 , 0.1, and 0.3) nanoplates primarily via dc magnetization, resistivity, and magnetoconductance measurements. The paramagnetism in the magnetic-atom-free Bi 2 Se 3 nanoplates is ascribed, using density functional theory calculations, to the acquisition of magnetic moments by defects. The defect density in pure Bi 2 Se 3 is estimated to be high (∼ 10 19 defects/cm 3). Successive Dy doping brings in further incremental disorder, apart from the Dy atomic moments. The nanoplates are shown to sequentially exhibit thermally activated band conduction, nearest neighbor hopping, Mott variable range hopping (VRH), and Efros–Shklovskii VRH with decreasing temperature. WL is evident from the observed positive magnetoconductance. Annealing converts the WL behavior to WAL, arguably by setting in the topological protection on a substantial reduction of the disorder. [ABSTRACT FROM AUTHOR]

We report the decoupling of Gd–Cr magnetism and the resulting giant magnetocaloric effect in honeycomb-lattice tellurate GdCrTeO6. This compound adopts the hexagonal structure with the space group P-3. The susceptibility curve presents a paramagnetic behavior from room temperature to 2 K. Very intriguingly, however, the heat capacity measurement probes a λ-like peak at TN = 10 K, characterizing the long-range antiferromagnetic order. This suggests that the Gd and Cr sublattices are magnetically independent, i.e., the Gd ions are paramagnetic and the strong paramagnetism nearly masks the antiferromagnetic order of Cr ions, which is further evidenced by our ESR data. The maximum magnetic entropy change at 2 K is 41.8 J kg−1 K−1 in a field range of 0–7 T and 30.3 J kg−1 K−1 for 0–3 T, larger than those of most of the Gd oxides reported. The observed giant magnetocaloric effect is due to strong paramagnetism of Gd ions. [ABSTRACT FROM AUTHOR]

Macroscopic compass‐like magnetic alignment at low magnetic fields is natural for ferromagnetic materials but is seldomly observed in paramagnetic materials. Herein, we report a "paramagnetic compass" that magnetically aligns under ~mT fields based on the single‐crystalline framework constructed by lanthanide ions and organic ligands (Ln‐MOF). The magnetic alignment is attributed to the Ln‐MOF's strong macroscopic anisotropy, where the highly‐ordered structure allows the Ln‐ions' molecular anisotropy to be summed according to the crystal symmetry. In tetragonal Ln‐MOFs, the alignment is either parallel or perpendicular to the field depending on the easiest axis of the molecular anisotropy. Reversible switching between the two alignments is realized upon the removal and re‐adsorption of solvent molecules filled in the framework. When the crystal symmetry is lowered in monoclinic Ln‐MOFs, the alignments become even inclined (47°‐66°) to the field. These fascinating properties of Ln‐MOFs would encourage further explorations of framework materials containing paramagnetic centers. [ABSTRACT FROM AUTHOR]

Macroscopic compass‐like magnetic alignment at low magnetic fields is natural for ferromagnetic materials but is seldomly observed in paramagnetic materials. Herein, we report a "paramagnetic compass" that magnetically aligns under ∼mT fields based on the single‐crystalline framework constructed by lanthanide ions and organic ligands (Ln‐MOF). The magnetic alignment is attributed to the Ln‐MOF's strong macroscopic anisotropy, where the highly‐ordered structure allows the Ln‐ions' molecular anisotropy to be summed according to the crystal symmetry. In tetragonal Ln‐MOFs, the alignment is either parallel or perpendicular to the field depending on the easiest axis of the molecular anisotropy. Reversible switching between the two alignments is realized upon the removal and re‐adsorption of solvent molecules filled in the framework. When the crystal symmetry is lowered in monoclinic Ln‐MOFs, the alignments become even inclined (47°‐66°) to the field. These fascinating properties of Ln‐MOFs would encourage further explorations of framework materials containing paramagnetic centers. [ABSTRACT FROM AUTHOR]

An analytical expression is found for the transverse dielectric permittivity of a nondegenerate electron plasma in the approximation of the effective collision frequency for a weakly nonideal gas, taking into account electron spin. The resulting expression takes into account both Landau diamagnetism and Pauli paramagnetism in an electron plasma. [ABSTRACT FROM AUTHOR]

We study the high and low-temperature thermo-statistical properties of ideal Fermi gases by taking into account the effect of generalized uncertainty principle (GUP). Starting with the logarithm of the grand partition function of ideal Fermi system, we derive the total number of particles, internal energy, entropy, and heat capacity under the GUP. For high temperatures, by obtaining a virial expansion of the equation of state of the system, the fist three virial coefficients are calculated. For low temperatures, by using the chemical potential of the system, the susceptibility for Pauli paramagnetism is derived. [ABSTRACT FROM AUTHOR]

The magnetic characteristics of a system of triply charged gadolinium ions Gd3+ chelated with carboxyls on the surface of detonation nanodiamond (DND) particles have been studied. Gd3+ ions demonstrate almost perfect spin (S = 7/2) paramagnetism with negligible antiferromagnetic interaction between spins (Weiss temperature about −0.35 K) for a wide range of concentrations up to ~18 ions per 5 nm particle. The study of the concentration dependence of the electron paramagnetic resonance signal for DND intrinsic defects with spin ½ (g = 2.0027) shows that Gd3+ ions are located on average at a distance of no more than 1.4 nm from shallow subsurface defects with spin 1/2. At the same time, they are located (according to density functional theory calculations) at a distance of about or at least 0.28 nm from the particle surface. Magnetic studies also confirm the isolated nature of the gadolinium chelate complexes on the surface of DND particles. DND particles turn out to be an optimal carrier for high-spin 4f- ions (gadolinium) in a highly concentrated isolated state. This property makes DND-Gd particles a candidate for the role of a contrast agent for magnetic resonance imaging. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the magnetic properties of mixed nanocrystalline Zn/manganese oxide compounds synthesized by a hydrothermal method. These compounds are designed as (ZnO)1−n(MnO)n, where index n ranges from 0.05 to 0.60. The results of magnetic measurements, including AC magnetic susceptibility as a function of temperature (up to 160 K) and frequency (from 7 Hz up to 9970 Hz), as well as DC magnetization in magnetic fields up to 9 T and temperature up to 50 K, are reported. We observed various types of magnetic behavior depending on the nominal weight content of MnO. Samples with a low nominal content (up to n = 0.10) of MnO exhibited Curie–Weiss behavior at higher temperatures. For samples with high nominal weight contribution (from n = 0.30 to 0.60), spin-glass-like or/and weak ferromagnetic behavior is observed. [ABSTRACT FROM AUTHOR]

A series of polynuclear Cu(II) complexes, namely, (Him)2[Cu2(pzdc)2(H2O)2] (1), [Cu3(pzdc)2(im)2(H2O)4] (2), {[Na4Cu4(pzdc)4(im)4(H2O)2]·16H2O}n (3), (Hamp)2[Cu2(pzdc)2(H2O)2] (4), (H2tmdp)2[Cu4(pzdc)4(H2O)2]·2H2O (5), {[Cu2(pzdc)2][Cu(H2O)6]}n (6), and [Cu3(pzdc)2(en)2(H2O)2]n (7), were successfully synthesized under the reaction of Cu(NO3)2·3H2O, pyrazole-3,5-dicarboxylic acid, and various ancillary ligands (im = imidazole, amp = 4-aminopyridine, tmdp = 4,4′-trimethylenedipyridine, and en= ethylenediamine). The magnetic study based on the secondary building Cu(II) unit with pyrazole-3,5-dicarboxylate bridges can be divided into three groups: (Group I) dinuclear Cu(II) units of 1, 4, and 6, (Group II) trinuclear Cu(II) units of 2 and 7, and (Group III) tetranuclear Cu(II) units of 3 and 5. The magnetic properties of 1 and 4 (group I) exhibit spin-canted antiferromagnetism while 6 exhibits typical antiferromagnetic coupling within the Cu(II) dimer with the paramagnetism from the [Cu(H2O)6]2+ unit. Group II exhibits antiferromagnetic interactions within the Cu(II) trimer for 2 and 7. Group III displays antiferromagnetic and weak ferromagnetic interactions within the tetranuclear Cu(II) unit. [ABSTRACT FROM AUTHOR]

Nitrogen-doped graphene quantum dots (NGQDs) have gained significant attention due to their various physical and chemical properties; however, there is a gap in the study of NGQDs' magnetic properties. This work adds to the efforts of bridging the gap by demonstrating the room temperature paramagnetism in GQDs doped with Nitrogen up to 3.26 at.%. The focus of this experimental work was to confirm the paramagnetic behavior of metal free NGQDs resulting from the pyridinic N configuration in the GQDs host. Metal-free nitrogen-doped NGQDs were synthesized using glucose and liquid ammonia as precursors by microwave-assisted synthesis. This was followed by dialysis filtration. The morphology, optical, and magnetic properties of the synthesized NGQDs were characterized carefully through atomic force microscopy (AFM), transmission electron microscopy (TEM)), UV-VIS spectroscopy, fluorescence, X-ray photon spectroscopy (XPS), and vibrating sample magnetometer (VSM). The high-resolution TEM analysis of NGQDs showed that the NGQDs have a hexagonal crystalline structure with a lattice fringe of ~0.24 nm of (1120) graphene plane. The N1s peak using XPS was assigned to pyridinic, pyrrolic, graphitic, and oxygenated NGQDs. The magnetic study showed the room-temperature paramagnetic behavior of NGQDs with pyridinic N configuration, which was found to have a magnetization of 20.8 emu/g. [ABSTRACT FROM AUTHOR]

The formation of catalytically active nano-sized cobalt-containing structures in multicomponent hydrogenation systems based on Co(acac)2 complex and various cocatalysts, namely, AlEt3, AlEt2(OEt), Li-n-Bu, and (PhCH2)MgCl, has been studied for the first time in detail using dynamic EPR spectroscopy. It is shown that after mixing the initial components, paramagnetic structures are formed, which include a fragment containing Co(0) with the electronic configuration 3d9, as well as a fragment bearing an aluminium, lithium, or magnesium atom, depending on the nature of the used cocatalyst. Such bimetallic paramagnetic sites are stabilized by acetylacetonate ligands. In addition, the paramagnetic complex contains the arene molecule(s), and the cobalt atom is bonded with the atom of the corresponding non-transition through the alkyl group of the co-catalyst, in particular through the carbon atom in the α-position with respect to the atom of the non-transition element. Due to the high reactivity of the described intermediates, they, under the conditions of hydrogenation catalysis, are transformed into nano-sized cobalt-containing structures that act as carriers of the catalytically active sites. Furthermore, because of the high reactivity and paramagnetism, such intermediates can be detected only by the EPR technique. The paper describes the whole experimental way of interpreting the EPR signals corresponding to the intermediates, precursors of catalytically active structures. In addition, a possible mathematical model based on the obtained experimental EPR data is presented. [ABSTRACT FROM AUTHOR]

Bi2Se3 has drawn great attention in current research for its novel topological property. In this literature, we establish the variation in structural, elemental, magnetic, and magneto-transport properties of Bi2Se3 due to the influence of Fe-doping. A solid-state synthesis mechanism has been used for the preparation of doped and un-doped Bi2Se3. Rietveld refinement of XRD data reveals the existence of Bi-substitution by Fe for low doping concentration. However, for high Fe-doping, there exists substitution of Bi as well as interstitial incorporation of Fe in host Bi2Se3. The XPS and SEM–EDX analysis also justify that Fe enters substitutionally for Bi and interstitial positions. From the magnetism study we have claimed that Fe-doped Bi2Se3 shows paramagnetism globally with local anti-ferromagnetism among Fe-dopants without long-range magnetic order. Based on electrical-transport survey we notice an increment of residual resistivity ( ρ 0) along with prominent anomaly in ρ xx –T profile around 120 K for high Fe-doping signifies the increment of carriers scattering. More importantly, there exists a gradual deviation of host quantum character, weak anti-localization (WAL) effect upon magnetic Fe-doping through the evidence of magneto-transport analysis. [ABSTRACT FROM AUTHOR]

Cubic-structured europium (Eu) doped zinc sulfide (ZnS) nanoparticles (NPs) were prepared via refluxing at 150 °C. Absolute structural studies showed that Eu+ ions were successfully substituted into the ZnS host lattice and changed the original structure of the host. As-fabricated ZnS:Eu NPs exhibited typical red emission due to the transition of the Eu dopant in the 5d0-7f1, 5d0-7f2, 5d0-7f3, and 5d0-7f4 energy levels of the 4f orbital of the dopant. The typical diamagnetic ZnS could be converted to tunable paramagnetic as a function of Eu-doping content. These NPs were quantified for hydrogen evolution through water splitting by artificial solar spectrum. Eu doping can drastically enhance the hydrogen (H2) evolution capability of ZnS, which is higher than that of bare ZnS NPs. The causes behind these engrossing results will be revealed. These interesting properties may find applications in optoelectronics, spintronics, and H2 evolution. [ABSTRACT FROM AUTHOR]

The A3M2M'O6 type materials Na3Ca2BiO6 and Na3Ni2BiO6 were successfully synthesised through two sol-gel techniques - a method based on a natural deep eutectic solvent, and a biopolymer-mediated synthesis. The materials were analysed using Scanning Electron Microscopy to determine if there was a difference in final morphology between the two methods, and it was found that the natural deep eutectic solvent method resulted in a more porous morphology. For both materials, the optimum dwell temperature was found to be 800 °C, which in the case of Na3Ca2BiO6 was a much less energy-intensive synthesis process than its seminal solid-state synthesis. Magnetic susceptibility measurements were undertaken on both materials. It was found that Na3Ca2BiO6 exhibits only weak, temperature independent paramagnetism. Na3Ni2BiO6 was found to be antiferromagnetic, with a Néel temperature of 12 K, in line with previously reported results. [ABSTRACT FROM AUTHOR]

In paramagnetic metalloproteins, longitudinal relaxation rates of 13C′ and 13Cα nuclei can be measured using 13C detected experiments and converted into electron spin-nuclear spin distance restraints, also known as Paramagnetic Relaxation Enhancement (PRE) restraints. 13C are less sensitive to paramagnetism than 1H nuclei, therefore, 13C based PREs constitute an additional, non-redundant, structural information. We will discuss the complementarity of 13C PRE restraints with 1H PRE restraints in the case of the High Potential Iron Sulfur Protein (HiPIP) PioC, for which the NMR structure of PioC has been already solved by a combination of classical and paramagnetism-based restraints. We will show here that 13C R1 values can be measured also at very short distances from the paramagnetic center and that the obtained set of 13C based restraints can be added to 1H PREs and to other classical and paramagnetism based NMR restraints to improve quality and quantity of the NMR information. [ABSTRACT FROM AUTHOR]

High-pressure neutron diffraction data from powder and single-crystal samples of atomically disordered (F m 3 ¯ m) and ordered (P m 3 ¯ m) Pd 3 Fe were collected up to pressures of 15 GPa, and high-pressure SQUID magnetometry data were collected up to 6 GPa. The data show a subtle decrease in the magnetic moment with applied pressure, resulting in a transition to a paramagnetic state by approximately 8 GPa at 300 K. Diffraction results have been used to determine the equation of state, resulting in a bulk modulus of 176.78(9) GPa for the disordered powder and 187.96(7) GPa for the ordered single-crystal samples, approximately 20% more compressible than previously reported from X-ray measurements. High-temperature superconducting quantum interference device magnetometry was used to confirm the ambient pressure Curie temperature of the sample (545 K), which was further investigated using high-temperature single-crystal neutron diffraction at ambient pressure. [ABSTRACT FROM AUTHOR]

Natural polymers have received a great deal of interest for their potential use in the encapsulation and transportation of pharmaceuticals and other bioactive compounds for disease treatment. In this perspective, the drug delivery systems (DDS) constructed by representative natural polymers from animals (gelatin and hyaluronic acid), plants (pectin and starch), and microbes (Xanthan gum and Dextran) are provided. In order to enhance the efficiency of polymers in DDS by delivering the medicine to the right location, reducing the medication's adverse effects on neighboring organs or tissues, and controlling the medication's release to stop the cycle of over- and under-dosing, the incorporation of Fe3O4 magnetic nanoparticles with the polymers has engaged the most consideration due to their rare characteristics, such as easy separation, superparamagnetism, and high surface area. This review is designed to report the recent progress of natural polymeric Fe3O4 magnetic nanoparticles in drug delivery applications, based on different polymers' origins. [ABSTRACT FROM AUTHOR]

NdFe1−xCoxO3 samples are prepared by the sol–gel method. The X‐ray diffraction (XRD) results show that these samples conform to the orthogonal perovskite structure (Pbnm), and different doping amounts can cause the patterns to shift by XRD pattern. Through the Williamson–Hall analysis, the microstrain of the lattice between different doping amounts was obtained, and the average crystal size was calculated. The element content of each sample was obtained by scanning electron microscope and energy‐dispersive X‐ray analysis. Mössbauer spectra show that different doping levels change the surrounding environment of iron, and the magnetic properties of the samples also change. [ABSTRACT FROM AUTHOR]

The results of a theoretical study of the role of water in electromagnetic generation and in the process of realizing the phenomenon of life are presented in the article. This article is a continuation of the theoretical study of the team of authors, which was published in the Journal of Complexity in Health Sciences, Vol. 5, Issue 1, 2022, p. 22-34. The aim of the theoretical study was to generalize the available scientific physical and biological knowledge of modern science about the role of water in the electromagnetic processes of the phenomenon of life at the cellular level in order to deepen the fundamental knowledge of Complex Medicine. This study is a fragment of research work on "Development of algorithms and technologies for implementing a Healthy Lifestyle in patients with Noncommunicable Diseases based on the study of functional status" (state registration number 0121U108237: UDC 613 616-056-06: 616.1/9-03). General scientific methods and theoretical methods were used in this theoretical study. The main conclusions of the theoretical study were made as follows: 1) The "30/11 helix" is the main most typical fragmentary element of water self-organization into fractal structures and it forms energyintensive fractal crystalline filamentous water structures in living biological systems, supported by energy constantly coming from biopolymers, and forming large constantly growing hierarchical structures that unite all the water of a living organism in a dynamic balance of opposite processes of destruction and growth of its energy-intensive crystalline structures; 2) Water has a key role in the process of transmission and perception of the coherent energy of a soliton through self-organizing fractal energy-intensive paramagnetic crystalline structures in living biological systems; 3) The phenomenon of biological life at the micro level is characterized by the presence of a state of water binding/organization into energy-intensive crystalline structures due to the constant supply of coherent energy from biopolymers and stops when this energy flow disappears, which corresponds to the onset of the phenomenon of biological death and is manifested by the degradation of energy-intensive fractal crystalline self-organization of water to an unbound water state. solution devoid of so-called biological anomalies. [ABSTRACT FROM AUTHOR]

Two unique spinel compounds of type NiRh2S4 and RhNi2S4 crystal structure with chemical formula AB2X4 (A = Ni, Rh; B = Rh, Ni; and X = S) are chosen for the first time due to their importance in catalyst reactions and interesting physical properties to explore their structural, mechanical, electronic, and magnetic properties. First principle treatment has been implemented for the above-mentioned compounds with full potential linearized augmented plane wave plus local orbital methods (FPLAPW + LO) within the exchange correlation potentials range of state of the art density functional theory (DFT). The results obtained for the structural properties of these compounds using GGA approximation are compared with already available experimental results in the literature. Our spotted lattice constants for NiRh2S4 and RhNi2S4 are found to be consistent with experiment. Additionally we have also implemented the GGA + U potential for the improvements of electronic and magnetic characteristics of the compounds under investigation. Centered on the magneto-electronic properties, these compounds are metallic and paramagnetic in nature. Moreover, the crystal field splitting and the elastic properties of NiRh2S4 and RhNi2S4 are also discovered. The studies reveal that these compounds are elastically stable and ductile in character. Metallic characteristics and paramagnetic behavior of the compounds under observation predict their importance in spintronic and acoustical devices. [ABSTRACT FROM AUTHOR]

The production of one-dimensional nanorods (NRs) has been capturing decent curiosity due to the peculiar electronic, spintronic, and hydrogen evolution properties. Consequently, herein, diluted magnetic semiconducting ZnO:V (0, 1, and 2 at%) NRs have been prepared through a typical hydrothermal method. SEM images depicted that the prepared samples belonged to nanorods. V ion incorporation into the ZnO matrix was confirmed through XRD, Raman, and XPS studies. A trivial decreasing of optical band gap with the V doping was determined via Kubelka–Munk plots. The doping enhances the paramagnetic nature of ZnO as function of V doping. Importantly, these NRs were measured for H2 production through H2O splitting by the solar simulator. The ZnO:V (2 at%) portrayed the best H2 production capability (25,188 µmol h−1 g−1) in 5 h than other samples. The plausible reasons behind the improved H2 evolution could be discussed in detail. Till date, this is the first ever report on H2 evolution of ZnO:V nanorods. [ABSTRACT FROM AUTHOR]

A first-order magneto-structural transition from a ferromagnetic orthorhombic TiNiSi-type martensite phase to a paramagnetic hexagonal Ni 2 In-type austenite phase was observed in (MnNiSi) 0.65 (Fe 2 Ge) 0.35 . In this work, we demonstrate that the first-order magneto-structural transition temperature for a given composition is tunable over a wide temperature range through heat treatment and hydrostatic pressure. The first-order transition temperature was reduced by over 100 K as the annealing temperature went from 600 to 900 °C, and this first-order transition was converted to second order when the sample was annealed at 1000 °C. The maximum magnetic-induced isothermal entropy change with μ 0 Δ H = 7 T reaches − 58 J/kg K for the sample annealed at 600 °C, and the relative cooling power reaches 558 J/kg for the sample annealed at 700 °C. Similar to the influence of annealing temperatures, the first-order martensitic transition temperatures were reduced as the application of hydrostatic pressure increased until they were converted to second order. Our results suggest that the (MnNiSi) 0.65 (Fe 2 Ge) 0.35 system is a promising platform for tuning magneto-structural transitions and the associated magnetocaloric effects. Furthermore, a similar heat treatment methodology or application of hydrostatic pressure can be applied to MnNiSi-based shape memory alloys to tailor their working transition temperatures. [ABSTRACT FROM AUTHOR]

In this paper, the magnetic and electrocatalytic properties of hydrothermally grown transition metal doped (10% of Co, Ni, Fe, and Mn) 2H-MoS2 nanocrystals (NCs) with a particle size 25–30 nm are reported. The pristine 2H-MoS2 NCs showed a mixture of canted anti-ferromagnetic and ferromagnetic behavior. While Co, Ni, and Fe doped MoS2 NCs revealed room temperature ferromagnetism, Mn doped MoS2 NCs showed room temperature paramagnetism, predominantly. The ground state of all the materials is found to be canted-antiferromagnetic phase. To study electrocatalytic performance for hydrogen evolution reaction, polarization curves were measured for undoped and the doped MoS2 NCs. At the overpotential of η = −300 mV, the current densities, listed from greatest to least, are FeMoS2, CoMoS2, MoS2, NiMoS2, and MnMoS2, and the order of catalytic activity found from Tafel slopes is CoMoS2 > MoS2 > NiMoS2 > FeMoS2 > MnMoS2. The increasing number of catalytically active sites in Co doped MoS2 NCs might be responsible for their superior electrocatalytic activity. The present results show that the magnetic order-disorder behavior and catalytic activity can be modulated by choosing the suitable dopants in NCs of 2D materials. [ABSTRACT FROM AUTHOR]

The crystal structure, and cryogenic magnetic and magnetocaloric properties in RE2T2Al (RE = Dy, Ho, Er, and Tm; T = Co and Ni) compounds have been investigated. All the compounds belong to an orthorhombic W2B2Co-type structure (Immm space group). A second order paramagnetic to ferromagnetic phase transition exists for RE2Co2Al compounds at TC = 62, 27, 32, and 11.5 K, whereas the compounds of RE2Ni2Al undergo a paramagnetic to antiferromagnetic phase transition with the Néel temperatures (TN) of 19, 12, 12.5, and 6 K for RE = Dy, Ho, Er, and Tm, respectively. Moreover, an additional low temperature magnetic transition occurs for all present RE2T2Al compounds. An obvious hysteresis was observed at a low temperature in the Dy2Co2Al, Ho2Co2Al, and Er2Co2Al compounds. The values of the maximum magnetic entropy change (−ΔSMmax) are 10.4, 11.5, 5.9, 7.7, 6.0, and 16.2 J/kg K for Dy2Co2Al, Ho2Co2Al, Er2Co2Al, Tm2Co2Al, Ho2Ni2Al, and Er2Ni2Al compounds with a field change (ΔH) of 0-5 T, respectively. Moreover, two peaks (or shoulder) in the −ΔSM (T) curves of Ho2Co2Al can be observed, which lead to a wide cooling temperature interval. [ABSTRACT FROM AUTHOR]

Enhancing the long term stable performance of silicon detectors used for monitoring the position and flux of the particle beams in high energy physics experiments requires a better knowledge of the nature, stability, and transformation properties of the radiation defects created over the operation time. We report the results of an electron spin resonance investigation in the nature, transformation, and long term stability of the irradiation paramagnetic point defects (IPPDs) produced by high fluence (2 × 1016 cm−2), high energy (27 MeV) electrons in n-type, P-doped standard floating zone silicon. We found out that both freshly irradiated and aged (i.e., stored after irradiation for 3.5 years at 250 K) samples mainly contain negatively charged tetravacancy and pentavacancy defects in the first case and tetravacancy defects in the second one. The fact that such small cluster vacancy defects have not been observed by irradiation with low energy (below 5 MeV) electrons, but were abundantly produced by irradiation with neutrons, strongly suggests the presence of the same mechanism of direct formation of small vacancy clusters by irradiation with neutrons and high energy, high fluence electrons, in agreement with theoretical predictions. Differences in the nature and annealing properties of the IPPDs observed between the 27 MeV electrons freshly irradiated, and irradiated and aged samples were attributed to the presence of a high concentration of divacancies in the freshly irradiated samples, defects which transform during storage at 250 K through diffusion and recombination processes. [ABSTRACT FROM AUTHOR]

The magnesium-rich intermetallic compounds RE3Ag4Mg12 (RE = Y, La–Nd, Sm–Dy, Yb) and AE3Ag4Mg12 (AE = Ca, Sr) were synthesized from the elements in sealed tantalum ampoules through heat treatment in an induction furnace. X-ray powder diffraction studies confirm the hexagonal Gd3Ru4Al12 type structure, space group P63/mmc. Three structures were refined from single crystal X-ray diffractometer data: a = 973.47(5), c = 1037.19(5) pm, wR2 = 0.0296, 660 F2 values, 30 variables for Gd3Ag3.82(1)Mg12.18(1), a = 985.27(9), c = 1047.34(9) pm, wR2 = 0.0367, 716 F2 values, 29 variables for Yb3Ag3.73(1)Mg12.27(1) and a = 992.41(8), c = 1050.41(8) pm, wR2 = 0.0373, 347 F2 values, 28 variables for Ca3Ag3.63(1)Mg12.37(1). Refinements of the occupancy parameters revealed substantial Ag/Mg mixing within the silver-magnesium substructure, a consequence of the Ag@Mg8 coordination. The alkaline earth and rare earth atoms build Kagome networks. Temperature dependent magnetic susceptibility measurements indicate diamagnetism/Pauli paramagnetism for the compounds with Ca, Sr, Y and YbII, while the others with the trivalent rare earth elements are Curie-Weiss paramagnets. Most compounds order antiferromagnetically at TN = 4.4(1) K (RE = Pr), 34.6(1) K (RE = Gd) and 23.5(1) K (RE = Tb) while Eu3Ag4Mg12 is a ferromagnet (TC = 19.1(1) K). 151Eu Mössbauer spectra confirm divalent europium (δ = −9.88(1) mm s−1). Full magnetic hyperfine field splitting (18.4(1) T) is observed at 6 K. Yb3Ag4Mg12 shows a single resonance in its 171Yb solid state NMR spectrum at 6991 ppm at 300 K indicating a strong, positive Knight shift. [ABSTRACT FROM AUTHOR]

In this work, we present eight oxamato complexes of formula (n-Bu4N)[M(HL)4(DMSO)]·nH2O (M = Y3+, La3+, Nd3+, Ho3+) with either _HClppa (= N-(4-chlorophenyl)oxamic acid) or _HFppba (= N-(4-fluorophenyl)oxamic acid) as the HL ligands, n = 2 (_HFppa) or 3 (_HClppa), besides the coordinated dimethylsulfoxide (DMSO) molecule, and tetrabutylammonium (n-Bu4N+) as counterions. All compounds were characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction. The analysis shows that all mononuclear compounds, with two oxygen atoms from each oxamic acid ligand and a DMSO molecule coordinated to the metal ion, result in a MO9 sphere of coordination. The dc magnetic properties of complexes Nd_HClppa, Nd_HFppa, Ho_HClppa, and Ho_HFppa reveal their paramagnetism. The ac magnetic measurements indicate the existence of slow relaxation of the magnetization for Ho3+ and Nd3+ compounds at low temperatures, suggesting that Ho3+ complexes are single-ion magnets (SIMs) while Nd3+ compounds are field-induced SIMs. Ab initio calculations were performed to determine the crystal-field parameters, which were subsequently used to obtain the best-fit curves of dc magnetic data and simulate susceptibility curves. The latter was consistent with experimental results for each compound, although small differences between compounds with the same lanthanide were not reproduced when all compounds were considered. [ABSTRACT FROM AUTHOR]

Imaging of magnetic nanoparticles with ultrasound utilizes ultrasound excitation and electromagnetic receiving. At present, the size of magnetic nanoparticles (MNPs) for the imaging method is required to be no less than 100 nm, which limits its application in human bodies. To overcome the limitation of particle size, imaging of MNPs with ultrasound based on saturation magnetization is proposed. The relationship between the concentration of superparamagnetic pear-shaped MNPs and the induced voltage under saturation magnetization is derived based on the classical Langevin theory of paramagnetism. A 3D simulation model is constructed and numerical research is carried out under the saturated magnetic field provided by the Helmholtz coil. The concentration image is reconstructed by point-by-point scanning. Numerical studies show that the induced voltage is rich in the concentration information of superparamagnetic pear-shaped MNPs, proving the feasibility of the method. The maximum induced voltage, which enhances the imaging effect, occurs under the minimum radius of the detection coil containing the region of interest. MNPs under 20 nm still meet the imaging requirements in the proposed method. This research pushes the imaging of MNPs with ultrasound based on saturation magnetization a further step forward to practical applications in the biomedical field. [ABSTRACT FROM AUTHOR]

The magnetic properties of the Fe1−xAgxCr2S4 (0 < x < 0.2) solid solution were investigated in the temperature range 4–300 K in a DC field of 0.1 and 45 kOe. Fe1−xAgxCr2S4 is characterized by the transition temperature from the paramagnetic to the ferromagnetic state (Tc) and the irreversibility temperature (Tirr). The replacement of iron with silver ions in Fe1−xAgxCr2S4 leads to an increase in the Curie temperatures from 185 K (x = 0) to 216 K (x = 0.2) and Tcusp from 45 K (x = 0) to 125 K (x = 0.2). A section of the Fe1−xAgxCr2S4 magnetic phase diagram in the region under study has been constructed. The diagram reveals the following regions: paramagnetic, ferromagnetic, region of conditionally recurrent spin-glass (SG), and below 10 K a region associated with orbital ordering. [ABSTRACT FROM AUTHOR]

The behavior of the N‐heterocyclic carbene (NHC) stabilized 'parent' phosphinidene [(sIDipp)PH] (Dipp=2,6‐di‐isopropylphenyl) towards 3d‐metal(II) hexamethyldisilazanides is described. This leads to formation of the three‐coordinated phosphinidene adducts [M{PH(sIDipp)}{N(SiMe3)2}2] (M=Mn−Co), as evidenced by X‐Ray diffraction analysis. In solution, all compounds exhibit strong paramagnetism that limited NMR spectroscopic examinations to cobalt. Here it shows that the system is coordinatively highly fluxional, which is mitigtated upon cooling. At low temperatures, small amounts of free phosphinidene becomes further evident by 31P NMR spectroscopy that implicates in part ligand coordination competes with [M{N(SiMe3)2}2] dimerisation and an overall weak binding of the phosphinidene ligand. The rapid chemical exchange is evidenced in the presence of an excess of phosphinidene or a phosphine (PCy3), whereas diethyl ether proved as a stronger donor ligand. [ABSTRACT FROM AUTHOR]

Tin-doped zinc sulfide was coated onto glass plates and subjected to a post-air annealing treatment at 300 °C for 2 h. The air-annealed thin films were characterized for observing the tailoring in structural, surface, chemical, optical, photoluminescence, and magnetic properties due to annealing. The properties of thin films after air-annealing were compared with as-synthesized Kumar et al. (J. Supercond. Novel Magn. 32(6), 1725-1734, 2019), and vacuum-annealed Kunapalli et al. (Opt. Mater.114, 110961, 2021) thin films. Annealing in presence of air leads to finer crystallite structures of ZnS thin films. The air annealing also enhanced the transmittance property of the thin films. Two prominent peaks at 420 nm and 440 nm were observed in photoluminescence spectra. From magnetic studies, it was found that the films were paramagnetic in nature, and magnetization increased with an increase in the applied field. [ABSTRACT FROM AUTHOR]

By the controlling of oxygen flow rate, the oxygen content has been altered in the (CoFeTaB)(100−x)Ox system, a newly reported possible magnetic semiconductor. The electric and magnetic properties of (CoFeTaB)(100−x)Ox films are dependent on the oxygen content of (CoFeTaB)(100−x)Ox films. The resistivity of the grown (CoFeTaB)(100−x)Ox films could be altered from 3.77×10−4 Ω⋅cm to insulator. Correspondingly, the magnetic behavior of the grown (CoFeTaB)(100−x)Ox films was varied from ferromagnetism to paramagnetism. The increase in the resistivity was mainly attributed to the enhanced oxidization of metal Co; and the magnetism conversion was resulted from the decrease of ferromagnetic Fe3+ and increase of paramagnetic Co2+ in the grown films. These findings provide the fundamental reference for tailoring the electric and magnetic properties of (CoFeTaB)(100−x)Ox materials for potential applications in spintronics. [ABSTRACT FROM AUTHOR]

Paramagnetic colloidal particles distributed along an ellipse are used as a model system to study the effects of curvature gradients on the structure and dynamics of colloids in curved manifolds. Unlike what happens for circular and spherical systems, in the present case, the equilibrium one-particle distribution function displays inhomogeneities due to the changing curvature along the ellipse. The ensuing effects on the two-body correlations are also analyzed, leading to the observation of anisotropic and long-ranged effects. Another noticeable consequence is the slowing down of the self-diffusion of these particles, which for large eccentricities may induce metastable states; this is evaluated by means of the time-dependent self-distribution. [ABSTRACT FROM AUTHOR]

We present a parallel implementation to compute electron spin resonance g-tensors at the coupledcluster singles and doubles (CCSD) level which employs the ACES III domain-specific software tools for scalable parallel programming, i.e., the super instruction architecture language and processor (SIAL and SIP), respectively. A unique feature of the present implementation is the exact (not approximated) inclusion of the five one- and two-particle contributions to the g-tensor [i.e., the mass correction, one- and two-particle paramagnetic spin-orbit, and one- and two-particle diamagnetic spin-orbit terms]. Like in a previous implementation with effective one-electron operators [J. Gauss et al., J. Phys. Chem. A 113, 11541-11549 (2009)], our implementation utilizes analytic CC second derivatives and, therefore, classifies as a true CC linear-response treatment. Therefore, our implementation can unambiguously appraise the accuracy of less costly effective one-particle schemes and provide a rationale for their widespread use. We have considered a large selection of radicals used previously for benchmarking purposes including those studied in earlier work and conclude that at the CCSD level, the effective one-particle scheme satisfactorily captures the two-particle effects less costly than the rigorous two-particle scheme. With respect to the performance of density functional theory (DFT), we note that results obtained with the B3LYP functional exhibit the best agreement with our CCSD results. However, in general, the CCSD results agree better with the experimental data than the best DFT/B3LYP results, although in most cases within the rather large experimental error bars. [ABSTRACT FROM AUTHOR]

SrTiO3 is a widely used substrate for the growth of other functional oxide thin films. The reactivity of the substrate with respect to the film during deposition, particularly with regard to redox reactions, has typically been glossed over. We demonstrate by depositing a variety of metals (Ti, Al, Nb, Pt, Eu, and Sr) and measuring the in situ core level spectra of both the metal and SrTiO3 that, depending on the oxide formation energy and work function of the metal, three distinct types of behavior occur in thin metal films on SrTiO3 (100). In many cases, there will be an interfacial layer of oxygen-deficient SrTiO3 formed at the interface with the overlying film. We discuss how this may affect the interpretation of the well-known two-dimensional electron gas present at the interface between SrTiO3 and various oxides. [ABSTRACT FROM AUTHOR]

The direct random phase approximation (RPA) and RPA with second-order screened exchange (SOSEX) have been implemented with complex orbitals as a basis for treating open-shell atoms. Both RPA and RPA+SOSEX are natural implicit current density functionals because the paramagnetic current density implicitly is included through the use of complex orbitals. We confirm that inclusion of the SOSEX correction improves the total energy accuracy substantially compared to RPA, especially for smaller-Z atoms. Computational complexity makes post self-consistent-field (post-SCF) evaluation of RPA-type expressions commonplace, so orbital basis origins and properties become important. Sizable differences are found in correlation energies, total atomic energies, and ionization energies for RPA-type functionals evaluated in the post-SCF fashion with orbital sets obtained from different schemes. Reference orbitals from Kohn-Sham calculations with semi-local functionals are more suitable for RPA+SOSEX to generate accurate total energies, but reference orbitals from exact exchange (non-local) yield essentially energetically degenerate open-shell atom ground states. RPA+SOSEX correlation combined with exact exchange calculated from a hybrid reference orbital set (half the exchange calculated from exact-exchange orbitals, the other half of the exchange from orbitals optimized for the Perdew-Burke-Ernzerhof (PBE) exchange functional) gives the best overall performance. Numerical results showthat the RPA-like functional with SOSEX correction can be used as a practical implicit current density functional when current effects should be included. [ABSTRACT FROM AUTHOR]