APPLICATIONS OF NMR SHIELDING CALCULATIONS IN GEOCHEMISTRY AND MINERALOGY

Tossell (1993a) studied F-bearing species in aluminosilicate glasses and tentatively identified a five coordinate species, with three F and three O bonded to Al, whose spectral parameters were consistent with a species seen in F and Al NMR. The methods used were rather crude (LORG with modest basis sets), but the basic idea was to constrain the local structure of the species using a number of different experimental properties, basically a blind men and el ephant approach to the problem. 

Kubicki et al. (1999) had applied a similar approach to the complexation of Al with carboxylate complexes in aqueous solution. They found in a number of cases that the 

Al NMR shifts calculated for various species, defined in terms of number of Al number of carboxylate and degree of protonation, were not consistent with the 

A promising area for computational studies involves the mechanisms for biomineralization or in general the effect of biogenic solution species upon the relative stabilities and morphologies of minerals. A first step in this area has been taken by Sahai 

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