Search results for "Susceptibility"
showing 10 items of 912 documents
Crystal structure, spectroscopic characterisation and magnetic properties of [Cu(BIP)(N3)]·H2O (BIP=3,3-bis(2-imidazolyl)propionate), a copper(II) po…
2001
Abstract The structure and the spectroscopic and magnetic properties of [3,3-bis(2-imidazolyl)propionato]azidocopper(II) monohydrate are described. The compound is built of [Cu(BIP)N3] entities which are connected through carboxylate groups from the BIP molecules —which act as a tridentate ligand—and asymmetrical μ-1,3-azido bridges, leading to a polymeric sheet-like structure. The copper atom is involved in a CuN3ON′ chromophore and lies in a distorted square-pyramidal environment. Both electronic and EPR spectra are indicative of an essentially dx2−y2 ground state for the copper(II) ions. Magnetic susceptibility measurements in the range 1.8–200 K show very weak antiferromagnetic exchange…
Oxalate, squarate and croconate complexes with bis(2-pyrimidylcarbonyl)amidatecopper(II): synthesis, crystal structures and magnetic properties
2005
Abstract The preparation and magnetic properties of three copper(II) compounds of formulae [Cu2(bpcam)2(H2O)2(C2O4)] (1), [Cu2(bpcam)2(H2O)4(C4O4)] · 10 H2O (2) and Cu2(bpcam)2(C5O5)(H2O)3 (3) [bpcam = bis(2-pyrimidyl)amidate, C 2 O 4 2 - = dianion of oxalic acid , C 4 O 4 2 - = dianion of 3 , 4 - dihydroxycyclobut - 3 - ene - 1 , 2 - dione and C 5 O 5 2 - = dianion of 4 , 5 - dihydroxycyclopent - 4 - ene - 1 , 2 , 3 - trione ] are reported. The structures of two of them (1 and 2) have been solved by single crystal X-ray diffraction and consists of centrosymmetric discrete copper(II) dinuclear units bridged by bis-bidentate oxalate (1) and bis-monodentate squarate (2), with the bpcam group …
Structure and magnetic properties of a linear oximato-bridged tetranuclear copper(II) complex
1998
Abstract The tetranuclear copper(II) complex of formula [Cu2(dmg)(Hdmg)(terpy)]2(ClO4)2 (1) (H2dmg = dimethylglyoxime and terpy = 2,2′:6′,2″-terpyridine) has been synthesized and its crystal structure determined by X-ray diffraction methods. It crystallizes in the triclinic system, space group P(−1), with a = 14.382(3), b = 13.728(3), c = 8.979(2) A, α = 96.99(2), β = 111.85(2), γ = 111.22(3)°, V = 1465.0(9) A3, Z = 1, Dc = 1.607 g cm−3, Mr = 1418.0, F(000) = 719, λ(Mo Kα) = 0.71073 A, μ(Mo Kα) = 16.61 cm−1 and T = 298 K. A total of 4891 reflections were measured over the range 2 ≤ θ ≤ 25° and 4393 of them were unique (I > 2.5σ(I) and used in the structural analysis. The structure of 1 may …
Ferromagnetic exchange in a twisted, oxime-bridged [mniii2] dimer
2012
Journal article The dimeric complex [MnIII2(Naphth-sao)2(Naphth-saoH)2(MeOH)2][middle dot]4MeOH (1[middle dot]4MeOH), acts as a simple model complex with which to examine the magneto-structural relationship in polymetallic, oxime-bridged MnIII complexes. Dc magnetic susceptibility studies reveal that ferromagnetic exchange is mediated through the heavily twisted Mn-O-N-Mn moiety (J = +1.24 cm-1) with magnetisation measurements at low temperatures and high fields suggesting significant anisotropy. Simulations of high field, high frequency EPR data reveal a single ion anisotropy, D(MnIII) = -3.94 cm-1. Theoretical studies on simplified model complexes of 1 reveal that calculated values of the…
Crystal structure and magnetic properties of (tris{4-[1-(2-methoxyethyl)imidazol-2-yl]-3-azabut-3-enyl}amine)iron(II) bis(hexafluoridophosph…
2019
The title compound, [Fe(C27H41N10O3)](PF6)2, is an example of an iron(II) spin-crossover compound. In this compound, C⋯F and CH⋯F/O contacts, present between the cations and anions, extend the structure into a three-dimensional supramolecular network.
Synthesis, characterization and magnetic study of two new octahedral iron(III) complexes with pendant zwitterionic Schiff bases
2016
Two Schiff bases, HL1 [2-((3-(dimethylamino)propylimino)methyl)-5-bromophenol] and HL2 [2-((2-(diethylamino)ethylimino)methyl)-6-methoxyphenol], have been employed to prepare two new octahedral iron(III) complexes, [Fe(HL1)2(N3)2]ClO4·2H2O (1) and [Fe(HL2)2(NCS)2]ClO4·H2O (2). Both complexes are characterized by spectral and elemental analyses. Single crystal X-ray diffraction studies confirm their structures. In both complexes, Schiff bases are trapped in their zwitterionic forms and coordinated to iron(III) only through the imine nitrogen and phenoxo oxygen, i.e., they behave as bi-dentate ligands, keeping the remaining potential donor sites pendant. The measurement of χM vs. T for both c…
Effects of Digital Elevation Model resolution on evaluation of landslide susceptibility with a logistic regression model.
2013
The use of statistical methods together with the GIS technologies is currently one of the most efficient tools in the assessment of landslide susceptibility. The correlation between the physical phenomenon and its triggering factors depends on several factors, including the resolution at which the elevation data are represented in a Digital Elevation Model (DEM). The resolution becomes increasingly important as the use of DEM data is extended for spatial prediction of terrain attributes such as slope, aspect, plan and profile curvature, etc., which are considered as triggering factors of the landslides. Many methods exist in scientific literature to capture and model the correlation between…
Optical investigation of spin-crossover in cobalt(II) bis-terpy complexes
2007
Abstract The spin transition of the [Co(terpy) 2 ] 2+ complex (terpy = 2,2′:6′,2″-terpyridine) is analysed based on experimental data from optical spectroscopy and magnetic susceptibility measurements. The single crystal absorption spectrum of [Co(terpy) 2 ](ClO 4 ) 2 shows an asymmetric absorption band at 14 400 cm −1 with an intensity typical for a spin-allowed d–d transition and a temperature behaviour typical for a thermal spin transition. The single crystal absorption spectra of suggest that in this compound, the complex is essentially in the high-spin state at all temperatures. However, the increase in intensity observed in the region of the low-spin MLCT transition with increasing te…
Deconstructing and reconstructing resilience: a dynamic network approach
2019
Resilience is still often viewed as a unitary personality construct that, as a kind of anti-nosological entity, protects individuals against stress-related mental problems. However, increasing evidence indicates that the maintenance of mental health in the face of adversity results from complex and dynamic processes of adaptation to stressors that involve the activation of several separable protective factors. Such resilience factors can reside at biological, psychological and social levels and may include stable predispositions (such as genotype or personality traits) and malleable properties, skills, capacities or external circumstances (such as gene expression patterns, emotion regulatio…
Magnetic transition metal complexes of tetrathiafulvalene (TTF) derivatives
1997
We have prepared and characterized the transition metal complexes of two different TTF derivatives. We have oxidized the different complexes with electrooxidation and chemical oxidation techniques and the results are discussed. The magnetic properties of the complexes have been studied. TTF-carboxylate chelates are not stable enough, but thioether-TTF shows promising charge transfer salts.