Lattice cadmium compounds

The work of this laboratory extends the defect treatment to intermetallie compounds. The experiments measure simultaneously both the cadmium vapor pressure and the composition at equilibrium for a series of only slightly different alloy compositions. The precision and the relative accuracy of the measurements are high the absolute values suffer from any starting composition uncertainty and from errors in the absolute vapor pressure of cadmium as determined by other techniques. The experimental method is described elsewhere in this symposium (6). It has proved possible to infer the concentration and identity of lattice defects by analyzing the experimental data following the analytical techniques described below. 

It will be seen from this table that the monohalides of the inert gases all would be unstable to decomposition into their elements and so obviously could not exist in an ionic lattice. However this is not so for the other monohalides all of which, with the exception of BeCl, BeBr, and Bel, are stable with respect to decomposition to the elements. In these compounds the question arises as to their stability with regard to their disproportionation. In the case of the alkaline earths, zinc and cadmium, the disproportionation reaction is... 

Kitazawa. T. Nishikiori. S. Kuroda. R. Iwamoto. T. Clathrate compounds of cadmium cyanide and related hosts with cristobalite-like lattice structures. J. Chem. Soc., Dalton Trans. 1994. 1029-1036. 

A similar relation is observed for the binaiy structure types YCde (SG.Im3,a = 1548.3 pm) (Larson and Cromer, 1971) and YbCdg (SG lm3, a = 1565.8 pm) (Palenzona, 1971), and temaiy YbAg2ln4 (Sysa et al., 1989). These structures are actually identical considering the lattice parameters, the space group symmetry, the sites, and the parameters of the atoms. In YbAg2ln4 the smaller silver and indium atoms are ordered, thus, it represents a temaiy ordered superstmcture of the binary ones. However, there is a difference between the binary compounds in YCdg one cadmium atom occupies the 24g site by about one third, and in... 

All measurements were performed on magnetically diluted single crystals. As diamagnetic host lattices the corresponding cadmium(II)-complexes and in one case also the corresponding platinura(II) complex were used. The analysed diamagnetic compounds had the following compositions ... 

Spin-lattice relaxation rates for cadmium in organometallic compounds have been measured for neat dibutylcadmium (13) (T 0.2 sec - 5 sec Temp = 228 K Bq = 2.1 Tesla) and dimethyl-, diethyl-, and dipropylcadmiura (15) (T = 3.5-0.6 sec Bq = 2.35 Tesla). From NOE measurement, neat dimethylcadmium experiences no dipolar relaxation (15). Mechanisms contributing to relaxation are thought to be chemical exchange and chemical shielding anisotropy however, their relative importance has not been published for these compounds. 

In comparison with the acid digestion method, the hydrogenation method is more susceptible to matrix interferences. Two types of interferences are possible. Samples containing zinc, cadmium or mercury cannot be analyzed, as the high volatility of these elements results in the formation of a metallic mirror on the cooler parts of the tubing, which partially or completely absorbs the released sulphide. Sulphur may also be retained in the sample because it is present in the form of sulphur compounds which are not reduced or decomposed, e.g. manganese sulphide, or is held in crystal lattices which do not allow sufficiently rapid diffusion of sulphur at the temperature of 1150°C. 

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