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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 paper presents a dual gravity model for a (2+1)‐dimensional system with a limit on finite charge density and temperature, which will be used to study the properties of the holographic phase transition to paramagnetism‐ferromagnetism in the presence of Horndeski gravity terms. In our model, the non‐zero charge density is supported by a magnetic field. As a result, the radius ρ/B$\rho /B$ indicates a localized condensate, as the Horndeski gravity parameter is increased, that is represented by γ. Furthermore, such condensate shows quantum Hall‐type behavior. This radius is also inversely related to the total action coefficients of our model. It is observed that increasing the Horndeski parameter decreases the critical temperature of the holographic model and leads to the harder formation of the magnetic moment at the bottom of the black hole. However, when removing the magnetic field, the ferromagnetic material presents a disorder of its magnetic moments, which is observed through the entropy of the system. The authors also found that at low temperatures, spontaneous magnetization and ferromagnetic phase transition. [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]

We report a new cancer imaging modality in the contrast of tissue intrinsic susceptibility property by computed inverse magnetic resonance imaging (CIMRI). In MRI physics, an MRI signal is formed from tissue magnetism source (primarily magnetic susceptibility χ) through a cascade of MRI-introduced transformations (e.g. dipole-convolved magnetization) involving MRI setting parameters (e.g. echo time). In two-step computational inverse mappings (from phase image to internal fieldmap to susceptibility source), we could remove the MRI transformations and imaging parameters, thereby obtaining χ-depicted cancer images (canχ) from MRI phase images. Canχ is computationally implemented from clinical cancer MRI phase image by CIMRI. As a result of MRI effect removal through computational inverse mappings, the reconstructed χ map (canχ) could provide a new cancerous tissue depiction in contrast of tissue intrinsic magnetism property (i.e. diamagnetism vs paramagnetism) as in an off-scanner state (e.g. in absence of main field B 0). Through retrospective clinical cancer MRI data analysis, we reported on the canχ method in technical details and demonstrated its feasibility of innovating cancer imaging in the contrast of tissue intrinsic paramagnetism/diamagnetism property (in a cancer tissue state free from MRI effect). [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]