Mossbauer spectroscopy hydrides

A98. N. N. Greenwood and T. C. Gibb, Mossbauer Spectroscopy. Chapman Hall, London, 1971. Chapter 9, pp. 221-238 Covalent iron compounds (41), treats binary carbonyls, carbonyl anions, hydride anions, substituted iron carbonyls, ferrocene and other 7r-cyclopentadienyl iron derivatives. 

The interaction of the actinides or of their hydrides with chalcogens or H2X, respectively, give a number of nonstoichiometric phases with a composition close to AnX, An2X3, A11X2, An2Xs, or A11X3. Their thermal stability decreases in the order S > Se > Te. The magnetic susceptibility and Mossbauer spectroscopy show that the latter compounds may be formulated as [An +]2(S )2(S-Sf-, [An +]2(S -)3(S-S)2-, and [An +](S2-)(S-S)2-. These compounds have coordination numbers of 8, 10, and... 

In most of the compounds investigated by means of Fe Mossbauer spectroscopy the H2 uptake was found to be aceompanied by a marked change of the isomer shift (IS). In all cases the IS in the hydrides takes more positive values than in uncharged compounds. These changes of the IS in the positive direction were found in quite a number of compounds. The IS data eollected in table 10 may serve to illustrate this behaviour. To permit a quick comparison between the various data we have transformed the IS values reported into values relative to a-Fe. 

There is no evidence from Mossbauer, IR, or NMR spectroscopy for self-association of the hydrides in the solid or solution states, or for the interaction of Bu3SnH with Lewis bases (e.g. Bu3PO, HMPTA, L ). 

In FS03H at -78 °C, the methyltin hydrides Me4 SnH react to give dihydrogen and the solvated cations Me4 SnH i+ which have been identified by NMR spectroscopy.73 If the solutions are then frozen to 77 K, the Mossbauer spectra show the presence of the stannyl fluorosulphonates Mc4 SnII OS()2F. 

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