Lithium four-hydrated

Lithium bromide. C.AS 7550-35-8) LiBr. mp 550 C, soluble in HyO or alcohols. The compound is very hygroscopic and forms four hydrates. Major use has heen in ubsoiplion-refrigeration air-conditioning systems in which H-O is the refrigerant—strong LiBr is used to absorb HyO vapor. 

The M+ ions are hydrated or generally solvated to rather indeterminate degrees and are best written as M+(aq) or M+(solv). Lithium salt hydrates seldom contain more than four water molecules and exceptions are probably attributable to hydration of the anions. Lithium ions in solution have the largest hydrated radius (Table 6-2). Li salts generally deviate from ideal... 

Figure 6. A low-energy structure (possibly a minimum) found for the four-hydrated lithium cation. The symmetric structure is of higher energy than this one, although there is no guarantee that the reported structure is a global mini-...

Figure 10. A snapshot of the four-hydrated lithium cation during a 300 K Monte Carlo simulation...

Table 1. Pertinent Geometric Data for the Four-hydrated Proton in Two Configurations, the Symmetric One Shown in Figures 7a and 7b and the Elongated One Shown in Figure 8, and Comparable Data for the Four-hydrated Lithium Cation, Figure 6...

Lithium hydroperoxide 1-hydrate is a white, crystalline compound, which belongs to the orthorhombic system (o = 7.92 A., b = 9.52 A., c — 3.20 A.).4 The calculated density with four molecules to the unit cell is 1.60.4 The measured density is 1.69. Additional water may be trapped mechanically to give compositions slightly above the 1-hydrate.4 The compound reacts spontaneously with atmospheric carbon dioxide to form lithium carbonate and release oxygen. It decomposes gradually on standing in a closed system at room temperature to lithium hydroxide 1-hydrate. 

Spectroscopy in the hydrogen-stretching region was applied to characterize proton and lithium-ion complexed valine complexes as a function of hydration with up to four water molecules [22], Although calculations and prior study by black-body infrared dissociation had suggested the possibility of zwitterions,... 

We list in Table 11 the Gibbs free energies for hydration (35) AG° and hydration numbers n for the alkali metal cations (the values for n are a combination of experimental determinations (17,36,37) and of personal choice between conflicting results ). Just like the gas-phase value (Table 8, for instance) the AG° values vary regularly with the ionic radius, the smallest ions being more strongly hydrated. Lithium ion owes to its very small radius an unusually small coordination sphere, consisting of only four water molecules in the primary hydration shell (37). 

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