A theoretical study of the acetate 13C chemical shift tensor in cadmium acetate dihydrate

Theoretical calculations of the 13C chemical shielding tensor were completed on different fragments of the crystal structure of cadmium acetate dihydrate using the GIAO method. The calculations show the need for including intermolecular interactions in order to reproduce the experimental 13C chemical shift tensors of charged species. When a large enough fragment of the crystal is included in the calculation, the RMS difference between the experimental and the theoretical chemical shift tensor is 7 ppm, in comparison to differences of 64–20 ppm for calculations on isolated acetate anions and on cadmium acetate with and without waters of hydration. This RMS difference of 7 ppm is comparable to that obtained by calculations on neutral organic molecules, completed using similar computational approaches but without the inclusion of any intermolecular interactions.