Layer selection effect on solid state 13C and 15N chemical shifts calculation using ONIOM approach

► Solid-state 13C and 15N chemical shifts of uracil and imidazole are calculated. ► The 32 different levels of theory are performed for chemical shift calculations. ► A 2-layer ONIOM method is used to calculate solid-state 13C and 15N chemical shifts. ► Wave function results and layer selection effects are analyzed by factorial design. ► Results confirm the reliability of the selected wave functions and layer selection.