Lithium magnetic susceptibility

Magnetic susceptibility and Li and magnetic resonance results of FePSj and their lithium intercalates reveal that iron remains in the high-spin divalent state. In Li NiPSj, electrons added by intercalation of lithium seem to go to the transition-metal 4s or higher empty sulphur orbitals. The disappearance of magnetism in Li NiPSj for x > 0.5 is not understood. 

More than 30 years ago, Scott, Obenhaus, and Wilson (135) suggested that for lithium chloride, a solute to solvent ratio of 1 10 corresponded to a definite composition, and they quoted earlier measurements (134) as indicating two distinct, definite values for the magnetic susceptibility of lithium chloride above and below the concentration, corresponding to a decahydrate in solution. Likewise, anomalies were also found in the density of such solutions. Scott, Obenhaus, and Wilson also quoted Hiittig and Keller (83) who found that the densities, refractive indices, and coefficient of extinction of lithium halide solutions showed discontinuous changes with concentration for molar ratios of water to solute of 6, 30, and 75. 

Fig. 27. The magnetic susceptibility of solutions of lithium in ammonia and in methylamine. The broken and solid lines indicate the predicted concentration variations of the susceptibility, based on an electron-gas picture in which electron-electron correlations are neglected (157a, 157b).

Removal of lattice oxygen from the surface of nickel oxide in vcumo at 250° or incorporation of gallium ions at the same temperature [Eq. (14)] causes the reduction of surface nickel ions into metal atoms. Nucleation of nickel crystallites leaves cationic vacancies in the surface layer of the oxide lattice. The existence of these metal crystallites was demonstrated by magnetic susceptibility measurements (33). Cationic vacancies should thus exist on the surface of all samples prepared in vacuo at 250°. However, since incorporation of lithium ions at 250° creates anionic vacancies, the probability of formation of vacancy pairs (anion and cation) increases and consequently, the number of free cationic vacancies should be low on the surface of lithiated nickel oxides. Carbon monoxide is liable to be adsorbed at room temperature on cationic vacancies and the differences in the chemisorption of this gas are related to the different number of isolated cationic vacancies on the surface of the different samples. 

The structure analysis of the dilithium pentalenediide 45 reveals a C2-sym-metric ion triplet with the two lithium cations located on opposite sides of the two different rings. The structural parameters were extremely well reproduced by ab initio calculations [35] (see Fig. 3). Both the experimental structural parameters and calculated magnetic susceptibility exaltation classify the 107r-elec-tron species 45 as an aromatic compound. Apparently, the lithium counterions in 45 do not exert any significant effect on the bond lenghts of the dianion 22. On the other hand, the antiaromatic pentalene 2 and its aromatic dication 22+ show the characteristic bond length alternation (Fig. 3) [35]. 

As mentioned above, Lio.ieZrNCl becomes superconducting below 13 K. On lithium intercalation of /3-HfNCl with lithium naphthalide/THF the color of the crystals changes from white to black, and the interlayer separation increases from 9.23 A to either 14.0 and 18.7 A, corresponding to single or bilayer arrangements of THF molecules. Resistivity data for the 18.7A phase of Lio.48(THF)j,HfNCl show a sharp drop at 25.5 K and zero resistance at 24.5 K. Superconductivity is confirmed by magnetic susceptibility measurements, which indicate that the compound is a bulk type II superconductor. The composition Lio.48(THF)3,HfNCl has the highest transition temperature in this class of superconductors. 

Lithium oxides of Pu, magnetic measurements and reciprocal molar susceptibility vs. 

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