Ammonia intercalation

In the example with aniline, the aniline vapor was provided by the equilibrium vapor liquid aniline. Vapor-phase intercalation can be done with compounds that are gases at room temperature and ambient pressure. The most common gas used for intercalation reactions is ammonia. Ammonia intercalation can be accomplished by exposing a host to the vapor generated by a concentrated aqueous ammonia solution. This multi-component vapor containing NH3(g), IfeOQj),... 

Figure 3.10 Three steps in preparing an ammonia intercalation reaction cell (a) introduction of ammonia (b) condensation into sidearm (c) sealing of sample cell and vaporization of ammonia.

This rapid intercalation-deintercalation of ammonia can form the basis for a chemical sensing device. Thomas and Cleary (1996) used Mn2 2S6, a layered material similar to PM2, as the host material for ammonia intercalation and showed a rapid change in the dielectric properties of the host upon exposure to ppm concentrations of ammonia. 

E.W. Ong, J. Eckert, L.A. Dotson Sc W.S. Glaunsinger (1994). Chemistry of Materials, 6, 1946-1954. Nature of guest species within alkaline-earth ammonia intercalates of titanium disulfide. 

The result is a compound expressed as [NH4],NH3,i, j)[TaS2] . In this case x 0.1. The ammonia intercalate appears as an ionic compound in which NH ions are solvated by a large amount of NH3 (Fig. 4). This scheme explains the orientation of the threefold axis of the NH3 molecules as a consequence of dipole interactions NH ions can be exchanged, and they play the role of A ions in the A -ammonia solvated compounds. Both NH3 and NH4 are highly mobile at RT. Deintercalation at higher temperature is associated with the decomposition of NH4 cations. 

H, FeTi, Iron titanium hydride, 22 90 H2FeO,jOs3Cij, Osmium, tridecacar-bonyldihydridoirontri-, 21 63 H2FeOuRujC 3, Iron, tridecacarbonyl-dihydridotriruthenium-, 21 58 HjO.jOSjRuC,], Osmium, tridecacarbonyl-dihydridomtheniumtri-, 21 64 H,N, Ammonia intercalate with HNbTiOj, 22 89... 

Procedure lb Ammonia Intercalate of Tantalum Disulfide as an Intermediate... 

Synthesis of the lithium-ammonia intercalate requires about 6 days to complete and involves about 12h of lab time. Preparation of the lithium... 

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