SCF Xα DW nuclear magnetic screening tensor calculations

Calculations have been performed on the nuclear magnetic screening tensors for molecules via perturbation theory and the Xα DW method, and a comparison is made with results from other methods. Although the absolute errors in the σμυ for the molecules are appreciable, the relative errors in determining the NR chemical shifts are much less (see for example, the shift for CO relative to CH4), which is a hopeful factor leading one to expect that Xα DW can be widely used in analyzing NMR spectra. At the same time, Xα DW can closely reproduces the σμυ anisotropy, which is particularly important for compounds such as V2O5 or its derivatives, which show very large anisotropy in the magnetic screening tensors.