Ge-73, Sn-119 and Pb-207: general cooperative effects of single atom ligands on the NMR signals observed in tetrahedral [MXnY4-n] (M = Ge, Sn, Pb; 1 <= n <= 4; X, Y = Cl, Br, I) coordination compounds of heavier XIV group elements

摘要

An inverse linear relationship between Ge-73, Sn-119 and Pb-207 NMR chemical shifts and the overall sum of ionic radii of coordinated halido ligands has been discovered in tetrahedral [MXnY4- n] (M = Ge, Sn, Pb; 1 <= n <= 4; X, Y = Cl, Br, I) coordination compounds. This finding is consistent with a previously reported correlation found in octahedral, pentacoordinate and square planar platinum complexes. The effect of the coordinated halido ligands acting on the metal as shielding conducting rings is therefore confirmed also by Ge-73, Sn-119 and Pb-207 NMR spectroscopy.