Li I LITHIUM IODIDE

Li I LITHIUM IODIDE 41.903 2.8091E-02 6.6308E-14 -8.7334E-17 4.1888E-20 298 742 solid... 

In aqueous solutions of low concentration, when theories of ionic conductivities are applicable, no ion pairs will be formed in the case of the lithium and sodium halides at room temperature. Even in 13.9 mol (kg H20)"1 LiCl aqueous solution where the molar ratio of LiCl to H20 is 1 4, essentially no ion pairs between Li+ and Cl- ions are formed around 25°C, according to an MD simulation (28). Formation of the 1 1 ion pair between Li+ and Cl in aqueous solution is, however, concluded in 18.5 mol (kg H20) 1 aqueous solution where the nLiCI h2o molar ratio is 1 3, which is close to the saturation concentration of LiCl in water (29). Formation of the 1 1 Li+ Cl" ion pair has been suggested by a neutron diffraction method (30), but the data derived from such measurements were not in good agreement with the simulation results. No evidence has been found for ion-pair formation between Li+ and I ions at 20 and 50°C in 2.78 and 6.05 mol (kg H20) 1 aqueous lithium iodide using the solution X-ray diffraction method (31). 

We present how to treat the polarization effect on the static and dynamic properties in molten lithium iodide (Lil). Iodide anion has the biggest polarizability among all the halogen anions and lithium cation has the smallest polarizability among all the alkaline metal cations. The mass ratio of I to Li is 18.3 and the ion size ratio is 3.6, so we expect the most drastic characteristic motion of ions is observed. The softness of the iodide ion was examined by modifying the repulsive term in the Born-Mayer-Huggins type potential function in the previous workL In the present work we consider the polarizability of iodide ion with the dipole rod method in which the dipole rod is put at the center of mass and we solve the Euler-Lagrange equation. This method is one type of Car-Parrinello method. 

Europium-activated lithium iodide (enriched in Li) as a scintillator can detect neutrons and gammas simultaneously (Mukhopadhyaya and Mchugh 2004 Syntfeld et al. 2005). Neutrons are detected via the reaction Li(n, t)ot -I- 4.78 MeV. The high-energy pulses from the neutron events can be well discriminated from the pulses stemming from the interactions with the gamma radiation. 

For a more detailed look at this reaction, iodomethane reacts with lithium metal, which is assumed to exist as a simple dimer (Li-Li). The products are lithium iodide and CHgLi (methyllithium, 33). When the lithium dimer comes close to the C-I bond of iodomethane, the polarized C-I bond induces a polarized Li-Li structure (an induced dipole) and the transition state of the reaction is taken to be 31. Rather than transferring two electrons, the Li-Li bond breaks with transfer of only one electron (homolytic cleavage remember that Li is in group 1), which leads to formation of a methyl radical ( 0113) and a lithium radical ( Li), as well as a lithium cation and an iodine anion (see 32). Transition state 31 represents the transfer of single electrons to generate radicals. When the methyl radical and the lithium radical combine, each donates... 

For halobenzenes, halogen-Li exchanges and benzyne formation become easier in the sequence I > Br > Cl > F indeed, for iodides and bromides, the most probable reactions are halogen-lithium exchanges (see 5.5.2.3.3.). Halogenoanisoles,... 

Same answer as problem 33 but with sodium ions, Na" ", instead of lithium ions, Li, and sulfate ions, S04 , in the place of iodide ions, I . 

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