Stannous compounds, isomer shift

The tin(n) oxidation state is comparatively unstable with respect to tin(TV), and relatively few compounds have been isolated. They are easily characterised in the Mdssbauer spectrum by their high positive chemical isomer shifts with respect to SnOa ( 2-3-4-1 mm s 0- However, the detailed interpretation of stannous chemical isomer shifts has so far not been achieved. Several interpretations have adopted the naive assumption that tin(II)... 

The situation for tin-119 is more confused because of the uncertainty in AR/R. The first attempts to systematize isomer shifts for tin-119 were made by Cordey-Hayes and his co-workers (8). He assumed that ionic stannous compounds have a configuration 5s, Sn compounds or tetrahedral tin compounds have the configuration in which there are 4 p ... 

One immediate question appears why the wide range of isomer shifts for stannous compounds The tin ions cannot be in the ideal Sn (5s ) state. What is happening All of these compounds have complicated crystal structures, with tin located at a site which does not have inversion symmetry there is an electric field acting at the site of the tin. This electric field produces matrix elements between the 5s and the 5p states of the tin and therefore a mixing of the two states. The ground state under these circumstances is not a pure 5s state, but a mixture of 5s and 5p. This is confirmed by studying the quadrupole splitting of... 

Relation between isomer shift and quadrupole splitting for stannous compounds (13)... 

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