Search results for "Magnetic Susceptibility"

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 …

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…

Accidentally on purpose: construction of a ferromagnetic, oxime-based [MnIII2] dimer

2011

The serendipitous self-assembly of the complex [Mn(III)(2)Zn(II)(2)(Ph-sao)(2)(Ph-saoH)(4)(hmp)(2)] (1),whose magnetic core consists solely of two symmetry equivalent Mn(iii) ions linked by two symmetry equivalent -N-O- moieties, provides a relatively simple model complex with which to study the magneto-structural relationship in oxime-bridged Mn(III) cluster compounds. Dc magnetic susceptibility measurements reveal ferromagnetic (J = +2.2 cm(-1)) exchange resulting in an S = 4 ground state. Magnetisation measurements performed at low temperatures and high fields reveal the presence of significant anisotropy, with ac measurements confirming slow relaxation of the magnetisation and Single-Mo…

Magnetism and EPR spectra of the two‐sublattice manganese chain Mn2(EDTA)⋅9H2O

1990

We report on the magnetic behavior and single‐crystal EPR spectra of the chain complex Mn2(EDTA)⋅9H2O characterized by two different alternating sites for the manganese ions. Magnetic susceptibility data are indicative of weak antiferromagnetic exchange interactions between the manganese ions, showing a maximum of about 3 K. This behavior can be accurately described on the basis of a Heisenberg chain model that assumes classical spins, giving J/k=−0.72 K and g=2.0. The EPR spectra are typically low dimensional, with an angular dependence of the linewidth of the type (3 cos2 θ−1)n (n=4/3 or 2). Nevertheless, such a behavior cannot be reproduced from a one‐dimensional model with dipolar broad…

Ferromagnetism in [Mn(Cp*) 2 ] + ‐Derived Complexes: the “Miraculous” Stacking in [Mn(Cp*) 2 ][Ni(dmit) 2 ]

2003

The synthesis and characterisation (X-ray structure and magnetism) of metal complexes (Ni, Au) with the [Mn(Cp*)2]+ cation and the dmit2− and dmid2− ligands are reported. [Mn(Cp*)2][Ni(dmit)2] (1) and [Mn(Cp*)2][Au(dmit)2] (2) exhibit the same structural arrangement, built on stacks of [Ni(dmit)2]− pairs separated by two [Mn(Cp*)2]+ cations, showing a ···D+D+A−A−D+D+A−A−··· motif. On the contrary, the dmid2− derivative [Mn(Cp*)2][Ni(dmid)2]·CH3CN (3) exhibits a totally different structure, built on mixed layers composed of one [Ni(dmid)2]− unit separated by two [Mn(Cp*)2]+ cations, showing a ···D+D+A−D+D+A−···motif. The layers are separated from each other by perpendicular [Ni(dmid)2]− unit…

Small clusters with Heisenberg antiferromagnetic exchange

2000

We study small symmetrical clusters of magnetic ions with Heisenberg antiferromagnetic exchange interaction. We calculate the magnetization and the specific heat as functions of applied magnetic field at zero and non-zero temperature. Results are given for both classical and quantum systems. At zero temperature the classical systems undergo a series of transitions where the symmetry changes as a function of applied field. The quantum systems show similar features to Ising systems previously studied.

Hexahalorhenate(iv) salts of protonated ciprofloxacin: antibiotic-based single-ion magnets

2021

Two novel Re(IV) compounds of formula [H2cip][Hcip][ReCl6]Cl·H2O (1) and [Hcip]2[ReBr6] (2) [(H2cip)2+/(Hcip)+ = ciprofloxacindiium cation / ciprofloxacinium cation] have been synthesized and studied structurally and magnetically. 1 crystallizes in the monoclinic system with space group P21/c, whereas 2 crystallizes in the orthorhombic system with space group Pbca. 1 and 2 are hexahalorhenate(IV) salts obtained with the protonated ciprofloxacin antibiotic. In their crystal lattice, the [ReX6]2− [X = Cl(1) and Br(2)] anions are well separated from each other through the protonated ciprofloxacindiium (1) and ciprofloxacinium (1 and 2) cations, which are arranged without generating intermolecu…

High nuclearity magnetic clusters: Magnetic properties of a nine cobalt cluster encapsulated in a polyoxometalate, [Co9(OH)3(H2O)6(HPO4)2(PW9O34)3]16⊕

1994

Magnetic properties and61Ni Mössbauer spectroscopy of the ternary phosphide CrNiP

2008

The results of x-ray diffraction, dc magnetization, and 61Ni Mossbauer spectroscopy studies of the ternary phosphide CrNiP are reported. This compound crystallizes in the orthorhombic Co2P-type structure (space group Pnma) with the lattice parameters a = 5.7965(1) A, b = 3.5337(1) A, and c = 6.8123(2) A. NiCrP is a ferromagnet with Curie temperature TC = 135.1(1) K. The ferromagnetic-to-paramagnetic transition is characterized by the critical exponents β = 0.355(22), γ = 1.241(18), and δ = 4.585(20). Their values are close to those of a 3D Heisenberg ferromagnet. The temperature dependence of the magnetic susceptibility above TC follows the modified Curie–Weiss law with a paramagnetic Curie…

LOCAL-MOMENT AND ITINERANT ANTIFERROMAGNETISM IN THE HEAVY-FERMION SYSTEM CE(CU1-XNIX)2GE2

1992

Elastic and inelastic neutron-scattering studies on the system Ce(Cu1−xNix)2Ge2 are reported. These measurements are complemented by measurements of the magnetic susceptibility, high-field magnetization, heat capacity, thermal expansion, electrical resistivity and thermopower. The results reveal an interesting T-x phase diagram consisting of two different antiferromagnetic phases for x 0.5. Further experimental evidence for different types of antiferromagnetic ordering derives from a line-shape analysis of the quasielastic neutron-scattering intensity, from magnetization and thermopower experiments.