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Updated: Feb 17, 2026
Analyzing Melts and Fluids from Ab Initio Molecular Dynamics Simulations with the UMD Package
Published on: September 17, 2021
Correlating geminal 2JSi-O-Si couplings to structure in framework silicates
D J Srivastava1, P Florian, J H Baltisberger
1Department of Chemistry and Biochemistry, 100 West 18th Avenue, Columbus, OH, USA. grandinetti.1@osu.edu.
Abstract:
The dependence of a 29Si geminal J coupling across the inter-tetrahedral linkage on local structure was examined using first-principles DFT calculations. The two main influences on 2JSi-O-Si were found to be a primary dependence on the linkage Si-O-Si angle and a secondary dependence on mean Si-O-Si linkage of the two coupled 29Si nuclei. An analytical expression describing these dependences was proposed and used to develop an approach for relating the correlated pair of 2JSi-O-Si coupling and mean 29Si isotropic chemical shift to the linkage Si-O-Si angle and the mean Si-O-Si angle of the two coupled 29Si nuclei. An example of this analysis is given using 29Si NMR results from the siliceous zeolite Sigma-2.
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