Search results for "Magnetism"
showing 10 items of 1934 documents
Synthesis and magnetic characterization of trans-dichloroplatinum blues with creatinine
1992
Abstract By reaction of trans -[Pt II Cl 4 ] 2− with the amidate ligand creatinine two new paramagnetic blue platinum complexes have been obtained, namely violet and green varieties. These complexes have been characterized from thermal analysis, EPR and magnetic susceptibility. The violet complex has been formulated as trans -[Pt(creat)(H 2 O)Cl] 4 Cl. This compound has shown to be very stable, showing an extensive hyperfine structure in the powder EPR spectra. This result is a clear evidence of a tetranuclear oligomeric structure with one delocalized unpaired spin in the unit. EPR spectra in frozen solutions indicate that this mixed-valence complex maintains its oligomeric structure upon d…
S29i attribution of the 1.3 mT hyperfine structure of the E′γ centers in amorphous SiO2
2009
We report an experimental investigation by electron paramagnetic resonance of the doublet of lines split by ∼1.3 mT and centered on the E′γ; center resonance line in the spectrum of irradiated amorphous SiO2 . Commercial and sol-gel materials, some of which subjected to hydrogen-deuterium exchange, were investigated. Exposure to γ or Β rays at room temperature of the samples and subsequent thermal treatments were carried out to induce the defects and to study their thermal stability. In all the materials used the ratio between the signal of the E′γ centers and that of the 1.3 mT doublet is constant and independent of the OH and OD contents. Furthermore, the 1.3 mT doublet and the E′γ center…
Uncompensated magnetization in the layered molecular antiferromagnet {N(n-C5H11)4[MnIIFeIII(ox)3]}∞
2009
Abstract Studies on the magnetic properties of the molecular antiferromagnetic material {N( n -C 5 H 11 ) 4 [Mn II Fe III (ox) 3 ]} ∞ , carried out by various physical techniques (AC/DC magnetic susceptibility, magnetization, heat capacity measurements and Mossbauer spectroscopy) at low temperatures, have been presented. Different experimental observations complement each other and provide a clue for the observation of an uncompensated magnetization below the Neel temperature and short-range correlations persisting high above T N . It is understood that the honeycomb layered structure of the compound contains non-equivalent magnetic sub-lattices, (Mn II –ox–Fe III A –...) and (Mn II –ox–Fe …
The Properties of Co2Cr1-xFexAl Heusler Compounds
2006
The classical concept of band structure tuning as used for semiconductors by partly replacing one atom by a chemical neighbor without altering the structure is applied examplarily to the half-metallic ferromagnetic Heusler compound Co 2 Cr 1 - x Fe x Al. Band structure calculations are presented for ordered and disordered compounds. We present experimental and theoretical results. The connection between specific site disorder and the band structure is shown explicitly with particular emphasis on the half-metallic properties. Experimentally observed deviations from the ideal Heusler structure and from the simple Slater-Pauling rule for the magnetization are discussed in close relation to the…
Search for Magnetic Monopoles with the MoEDAL Forward Trapping Detector in 13 TeV Proton-Proton Collisions at the LHC
2017
MoEDAL is designed to identify new physics in the form of long-lived highly-ionising particles produced in high-energy LHC collisions. Its arrays of plastic nuclear-track detectors and aluminium trapping volumes provide two independent passive detection techniques. We present here the results of a first search for magnetic monopole production in 13 TeV proton-proton collisions using the trapping technique, extending a previous publication with 8 TeV data during LHC run-1. A total of 222 kg of MoEDAL trapping detector samples was exposed in the forward region and analysed by searching for induced persistent currents after passage through a superconducting magnetometer. Magnetic charges excee…
Topological–chiral magnetic interactions driven by emergent orbital magnetism
2019
Two hundred years ago, Ampère discovered that electric loops in which currents of electrons are generated by a penetrating magnetic field can mutually interact. Here we show that Ampère’s observation can be transferred to the quantum realm of interactions between triangular plaquettes of spins on a lattice, where the electrical currents at the atomic scale are associated with the orbital motion of electrons in response to the non-coplanarity of neighbouring spins playing the role of a magnetic field. The resulting topological orbital moment underlies the relation of the orbital dynamics with the topology of the spin structure. We demonstrate that the interactions of the topological orbital …
Coordination Complexes of a Neutral 1,2,4-Benzotriazinyl Radical Ligand: Synthesis, Molecular and Electronic Structures, andMagnetic Properties
2015
A series of d-block metal complexes of the recently reported coordinating neutral radical ligand 1-phenyl-3-(pyrid-2-yl)-1,4-dihydro-1,2,4-benzotriazin-4-yl (1) was synthesized. The investigated systems contain the benzotriazinyl radical 1 coordinated to a divalent metal cation, MnII, FeII, CoII, or NiII, with 1,1,1,5,5,5-hexafluoroacetylacetonato (hfac) as the auxiliary ligand of choice. The synthesized complexes were fully characterized by single-crystal X-ray diffraction, magnetic susceptibility measurements, and electronic structure calculations. The complexes [Mn(1)(hfac)2] and [Fe(1)(hfac)2] displayed antiferromagnetic coupling between the unpaired electrons of the ligand and the meta…
Introducing coherent time control to cavity magnon-polariton modes
2020
By connecting light to magnetism, cavity-magnon-polaritons (CMPs) can build links from quantum computation to spintronics. As a consequence, CMP-based information processing devices have thrived over the last five years, but almost exclusively been investigated with single-tone spectroscopy. However, universal computing applications will require a dynamic control of the CMP on demand and within nanoseconds. In this work, we perform fast manipulations of the different CMP modes with independent but coherent pulses to the cavity and magnon system. We change the state of the CMP from the energy exchanging beat mode to its normal modes and further demonstrate two fundamental examples of coheren…
<title>Influence of strong static magnetic field on human cancer HT 1080 cells</title>
2001
The aim of this study was to investigate strong uniform magnetic field influence on the human cancer cells HT 1080. The cells were treated with magnetic field of intensity 1,16 Tesla and with anticancer agent - cis-platinum 0.025 mg/ml or vincristinum 2-3 ng/ml. The intact and the treated cell samples were incubated in a medium with acridine orange (AO). The magnetic field after 15 minutes of influence significantly increased cytoplasmic red fluorescence. Increased AO accumulation in lysosomes suggested to cancer cell metabolic activity stimulation.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Magnetic interface formation at Fe/Cr/Fe(100)
1997
Photoemission magnetic dichroism of Fe and Cr 3p core levels was employed to investigate the magnetic order at the Fe/Cr/Fe(100) interface. For submonolayer and monolayer Fe coverages on Cr(100) the interface system appears magnetically frustrated, with no net magnetization along the parallel (antiparallel) direction of the substrate magnetization. The analysis of the Fe 3p photoemission dichroism allows to conclude that, at these low coverages, Fe is magnetically ordered but along an axis lying at 90° from the substrate Fe(100) magnetization, favoring the interpretation of biquadratic coupling between the ultrathin iron overlayer and the bulk iron substrate, across the Cr interlayer.