Figure 5.

Different methods were employed to predict the shift result and result in unique trend lines for the ¹³C shielding-shift correlation plots. The linear fit parameters can deviate significantly from their ideal values (solid black line) of −1 for slope and 188 ppm for the ¹³C shielding of TMS reference for the different levels of theory and can be dependent on the bonding type of the molecules. While the ¹³C shielding-shift correlation for the lattice-including GIPAW PBE∕Fine (blue and magenta) method shows an improved scatter over the GIAO PBE1∕6-31G(d) method (cyan and red), the divergent trend lines for the carbohydrate and aromatic tensors are apparent.