EPR and Magnetic Studies on y:bis(N -Methyl Salicylaldimine) Copper(II)

EPR and magnetic studies on single crystals of the dimeric copper (II) compound y: his (N-methyl salicylaldimine) Cu(II) down to 1.5 K reveal that each Cu(II) dimer is ferromagnetically exchange coupled having negligible interdimer exchange interaction. The magnetic properties are best described with C4v ligand field symmetry around each Cu(II) ion. The principal axes of the susceptibility and the g-tensor are not strictly coincident at low temperature. EPR und magnetische Untersuchungen an Einkristallen der dimeren Kupfer (II)-Verbindung y: bis-(N-methylsalizylaldimin)- Cu(II) his herab zu 1,5 K zeigen, daB jedes Cu(II)-Dimer ferromagnetisch austauschgekoppelt ist und eine vernachlassigbare interdimere Austauschwechselwirkung aufweist. Die magnetischen Eigenschaften lassen sich am besten mit C4v-Ligandensymmetrie urn jedes Cu(II)-Ion beschreiben. Die Hauptachsen des Suszeptibilitats- und g-Tensoren sind nicht genau koinzident bei tiefen Temperature

Electron Paramagnetic Resonance Study of Copper(II) Fluosilicate Hexahydrate

An electron paramagnetic resonance study was performed on single crystals of copper fluosilicate hexahydrate. EPR signals correspond to three tetragonally distorted pctahedral Cu(II) ions (A site) with g values: g11 = 2.390, gJ. .= 2.093, and ·one regular octahedral Cu(II) ion (B site) with g = 2.093. The spectra are thus quite different from those observed earlier by Bleaney and Ingram in Cu(II):ZnSiF6 • 6H20. Fluosilicate hexahydrates of divalent metals belong to a series of crystals wellsuited for X-ray, magnetic susceptibility and anisotropy, electron paramagnetic resonance, optical, and other studies (J-4). Observations of an isotropic EPR signal at 90 K and above and anisotropic EPR signals at 20 K by Bleaney and Ingram (J) in Cu:ZnSiF6 • 6H20 provided the first experimental evidence of the Jahn-Teller effect. A determination of crystal structures of this series by Ray eta/. (2, 3) has revealed that copper(II) fluosilicate hexahydrate (3), contrary to earlier belief, is not isomorphous with zinc fluosilicate hexahydrate. The structure is still rhombohedral (space group R3) with a cell four times as large as that supposed earlier. The unit cell, which has dimensions a = b = 18.18 A and c = 9.857 A, contains three magnetically nonequivalent tetragonally distorted Cu(II) · 6H20 octahedra (Cu-0(1) = 1.97 A, Cu-0(2) = 1.97 A, Cu-0(3) = 2.367 A) designated as the A sites; and one regular Cu(II) · 6H20 octahedron (Cu-0 = 2.074 A) designated as the B site. It was therefore considered of interest to study EPR in single crystals of copper fluosilicate hexahydrate with the object of unravelling the nature of the ligand fields in a crystal where two types of Cu(II) complexes coexist

Toda Lattice Models with Boundary

We consider the soliton solutions in 1- and (1+1)-dimensional Toda lattice models with a boundary. We make use of the solutions already known on a full line by means of the Hirota's method. We explicitly construct the solutions satisfying the boundary conditions. The ${\bf Z}_{\infty}$-symmetric boundary condition can be introduced by the two-soliton solutions naturally.Comment: 9 pages, latex, no figure

Direct Calculation of Breather S Matrices

We formulate a systematic Bethe-Ansatz approach for computing bound-state (``breather'') S matrices for integrable quantum spin chains. We use this approach to calculate the breather boundary S matrix for the open XXZ spin chain with diagonal boundary fields. We also compute the soliton boundary S matrix in the critical regime.Comment: 23 pages, LaTeX, 1 eps figur

Customised structural, optical and antibacterial characteristics of cinnamon nanoclusters produced inside organic solvent using 532 nm q-switched nd:yag-pulse laser ablation

Biomedical values of organic natural cinnamon that are buried in their bulk counterpart can be exposed and customised via nanosizing. Based on this factor, a new type of spherical cinnamon nanoclusters (Cin-NCs) were synthesised using eco-friendly nanosecond pulse laser ablation in liquid (PLAL) approach. As-grown nontoxic Cin-NCs suspended in the citric acid of pH 4.5 (acted as organic solvent) were characterised thoroughly to evaluate their structural, optical and bactericidal properties. The effects of various laser fluences (LF) at the fixed wavelength (532 nm) on the physiochemical properties of these Cin-NCs were determined. The FTIR spectra of the Cin-NCs displayed the symmetric-asymmetric stretching of the functional groups attached to the heterocyclic/cinnamaldehyde compounds. The HR-TEM image of the optimum sample revealed the nucleation of the crystalline spherical Cin-NCs with a mean diameter of approximately 10 ± 0.3 nm and lattice fringe spacing around 0.14 nm. In addition, the inhibition zone diameter (IZD) and optical density (OD600) of the proposed Cin-NCs were measured to assess their antibacterial potency against the Staphylococcus aureus (IZD ≈ 24 mm) and Escherichia coli (IZD ≈ 25 mm) bacterial strains. The strong UV absorption (in the range of 269 and 310 nm) shown by these NCs was established to be useful for the antibacterial drug development and food treatment

NS Fivebrane and Tachyon Condensation

We argue that a semi-infinite D6-brane ending on an NS5-brane can be obtained from the condensation of the tachyon on the unstable D9-brane of type IIA theory. The construction uses a combination of the descriptions of these branes as solitons of the worldvolume theory of the D9-brane. The NS5-brane, in particular, involves a gauge bundle which is operator valued, and hence is better thought of as a gerbe.Comment: 20 pages, harvma

Exact noncommutative solitons in p-adic strings and BSFT

The tachyon field of p-adic string theory is made noncommutative by replacing ordinary products with noncommutative products in its exact effective action. The same is done for the boundary string field theory, treated as the p -> 1 limit of the p-adic string. Solitonic lumps corresponding to D-branes are obtained for all values of the noncommutative parameter theta. This is in contrast to usual scalar field theories in which the noncommutative solitons do not persist below a critical value of theta. As theta varies from zero to infinity, the solution interpolates smoothly between the soliton of the p-adic theory (respectively BSFT) to the noncommutative soliton.Comment: 1+14 pages (harvmac b), 1 eps figure, v2: references added, typos correcte

The continuum limit of the integrable open XYZ spin-1/2 chain

We show that the continuum limit of the integrable XYZ spin-1/2 chain on a half-line gives rise to the boundary sine-Gordon theory using the perturbation method.Comment: 8pages, LaTeX; typos in eq.(11) removed, one in reference correcte