Different potassium salts and zinc(II) and nickel(II) O,O'-dialkyldithiophosphate complexes were studied by solid-state P-31 CP/MAS and static NMR and ab initio quantum mechanical calculations. Spectra were obtained at different spinning frequencies, and the intensities of the spinning sidebands were used to estimate the chemical shift anisotropy parameters. Useful correlations between the shapes of the P-31 chemical shift tensor and the type of ligand were found: terminal ligands have negative values of the skew kappa, while bridging and ionic ligands have positive values for this parameter. The experimental results were compared with known X-ray diffraction structures for some of these complexes as well as with ab initio quantum mechanical calculations, and a useful correlation between the delta(22) component of the P-31 chemical shift tensor and the S-P-S bond angle in the O,O'-dialkyldithiophoshate zinc(II) and nickel(II) complexes was found: delta(22) increases more than 50 ppm with the increase of S-P-S bond angle from ca. 100degrees to 1201, while the other two principal values of the tensor, delta(11), and delta(33), are almost conserved. This eventually leads to the change in sign for kappa in the bridging type of ligand, which generally has a larger S-P-S bond angle than the terminally bound O,O'-dialkyldithiophoshate group forming chelating four-membered P<(S)(S)>Me heterocycles.