Hexammine Nickel Complex: Cooperative Rotation of Six NH3\text{}_{3} Groups

Electrostatic interactions between NH3 groups undergoing a correlated rotation are calculated with reference to the nickel hexammine complexes [Ni(NH$\text{}_{3}$)$\text{}_{6}$]$\text{}^{2+}$ The results demonstrate the angular dependence of the cis and trans arrangements of the model ammonia triangles. The previously defined four maxima and four minima are identified

Wavelet Analysis in EPR Spectroscopy

Possibility of application of wavelet analysis in EPR spectroscopy is investigated. Basic mathematics of the method is summarized, with emphasis on the relation between EPR experiment and physical interpretation of wavelet transform. The fact that first derivative of the Lorentzian function can be used as a base wavelet is employed and the specific rules of the interpretation of the final wavelet synthesis are identified. Analysis of a sample EPR spectrum of X-ray irradiated guanidinium aluminium sulphate hexahydrate crystal is given as an example. Set of parameters resulting from the wavelet analysis is subsequently used to reconstruct/synthesize the original EPR spectrum. The method involves an opportunity of eliminating unwanted components of the multicomponent spectra. Generally, the method may supplement other means of data analysis, in particular, in magnetic resonance

Temperature Dependence ofĝ Tensor Anisotropy in (tm-p-PD):Chloranil, Charge Transfer Complex Powders

The powders of 2,3,5,6-tetramethyl-p-phenylenediamine:chloranil charge transfer complex were studied by EPR. Numerical pack EPR-NMR was used to simulate and fit the X-band experimental data in the temperature range of 119-298 K. Very good agreement between the experiment and simulations permits to obtain the main values ofĝ matrix and plot their temperature dependence. At 150 K the main g values are g$\text{}_{xx}$=g$\text{}_{yy}$=2.0041 and g$\text{}_{zz}$=2.0015. g splitting factor varies significantly with temperature and shows an anomaly near 200 K. The signal narrows with the temperature increase, which agrees with the earlier observation. Individual component linewidth, used in the simulation is anisotropic and amounts to 0.1-0.8 mT; which is reasonable when compared with those measured earlier for the single crystals of p-phenylenediamine:chloranil, where the narrowest lines are quoted to be 18μT