The high spin complex Fe(I1) (N, N'-dicyclohexylthiourea)~(C10~)~ exists in two forms which only differ in the distortion from octahedral symmetry of the environment of the Fe ion. Thermodynamic data for the transformation from one form to the other as obtained from Mossbauer spectroscopy are presented and a method to derive kinetic parameters is described.

The structural transformation of substituted hexagonal ferrite powders BaFetoCoTiO~s prepared by mechanical milling, was investigated as a fimction of grinding time by means of MOssbauer spectrometry and static magnetic measurements. A spin reorientation is clearly evidenced from the temperature dependence of the hyperfine parameters and of the initial magnetic permeability on the powder mechan...

We have seen, by Mossbauer spectroscopy, magnetization and resistivity, changes on the physical properties of the aFe20Ni6oB20 alloy induced by thermal relaxation, notedly increases in T, and resistivity. These changes can be explained by modifications of the chemical short range order around Fe favouring the formation of Fe-Ni pairs.

A potters clay from the Gorgan plain, in N. E. Iran, has been fired successively at temperatures up to the melting point 1 200 "C in an atmosphere of air or 5 % CO in moist COz. Mossbauer spectra at 296 K and 4.2 K allow the determination of the relative amounts of iron in well-crystallised haematite or magnetite, of poorly-crystallised and fine-particle ferric oxide or hydroxide, and of iron d...

The Hilbert-Huang transform is applied to analyze single-particle Lagrangian velocity data from numerical simulations of hydrodynamic turbulence. The velocity trajectory is described in terms of a set of intrinsic mode functions C(i)(t) and of their instantaneous frequency ω(i)(t). On the basis of this decomposition we define the ω-conditioned statistical moments of the C(i) modes, named q-orde...

We present here a detailed time-dependent density-functional theory investigation aimed at systematically dissecting the electronic spectra of two thiolate and phosphine protected undecagold nanoclusters. Calculations performed on the experimental structures of Au11(PPh3)7Cl3 and Au11(PPh3)7(SPyr)3 show that ligands have negligible contributions in the visible region. Metal → ligand charge tran...

Setting up a system for first order results is straightforward. One can easily identify the major constituents in simple samples and obtain approximate concentrations. This is sufficient for some applications. However, second order effects are quite important for many applications. To obtain high accuracy, identify constituents with low concentrations, or operate on a wide variety of samples, s...

The prototropic exchange equilibria of two drugs, nizatidine (I) and ranitidine(II), and also of structurally related the N,N'-dimethyl-2-nitro-1,1-ethenediamine molecule (III) were investigated. From the changes in electronic spectra in media of various acidity several protonation constants were determined. For pK values were -0.82, 1.95, and 6.67; for ranitidine pK values were 1.95 and 8.13; ...

-Inelastic neutron scattering has been used to measure the linewidth of the dynamical response of Fe impurities in Mol-,Nb, alloys. The character of the local moment, inferred from its relaxation rate, does not change significantly up to x = 0.15. Between x = 0.15 and x = 0.30 the response decreases rapidly and has disappeared by x = 0.45. The magnetic character of dilute Fe impurities in solid...