²⁹Si NMR shielding tensors in triphenylsilanes - ²⁹Si solid state NMR experiments and DFT-IGLO calculations

²⁹Si NMR shielding tensors of a series of triphenylsilanes Ph ₃SiR with R = Ph, Me, F, Cl, Br, OH, OMe, SH, NH ₂, SiPh ₃, C≡CPh were determined from ²⁹Si CP/MAS spectra recorded at low spinning rates. In addition the principal components of the shielding tensor were calculated employing the DFT-IGLO method. For most silanes experimental and calculated values are in good accordance. Larger differences were observed for systems with hydrogen bridge forming substituents and the halides bromide and chloride. In some of the spectra the shielding information interfered with residual dipolar couplings. The different contributions of the various substituents to the principal components of the shielding tensor and the orientation of the tensor within the molecules are discussed and compared for the compounds under investigation.