Hydrolysis of the heavy metal cations: Relativistic effects

Abstract

The relativistic spin-averaged Douglas–Kroll theory at the level of the MP2 approximation has been applied to explain the hydrolysis trends for the Group 11 and Group 12 cations through the investigation of the structure and energetics of the Cu(H₂O)⁺, Ag(H₂O)⁺, Au(H₂O)⁺, Zn(H₂O)²⁺, Cd(H₂O)²⁺, and Hg(H₂O)²⁺ complexes. The parallel nonrelativistic calculations show that the anomalous features of the hydrolysis of the heaviest metal cations are primarily due to their strongly relativistic character and cannot be explained in the framework of the nonrelativistic theory. The complexes of the heaviest cations in the investigated series show a marked relativistic effect on the geometry and force constants.