Abstract

Application of the planar superatom model to describe the electronic structure, and to gain insights into the stabilization of metal macrocycles supporting closed-shell d(10)-d(10) interactions, is studied through analysis of the membered ring composed by Hg(II) atoms, namely, [Hg(C(CF3)(2))](5). Its electronic structure resembles the level sequence given for a planar jellium model, revealing an electronic configuration given by 1s(2) 1p(4) (x,y) 1d(4) (xy,x2-y2). The analysis of the population of each level of the Hg-5 core, denotes a slight net bonding into the [Hg(C(CF3)(2))](5) ring. However, stabilization is mainly supported by the balance given by a similar population of the jellium levels, which is suggested to be a different scheme for stabilizing d(10) macrocyclic clusters with metallophilic interactions, in the category of long d(10)-d(10) contacts. The extension of the planar jellium model to the relativistic case, including spin-orbit coupling considering the D-5h* point group, denotes the consequent splitting for levels with l not equal 0, namely, 1p(x,y) and 1d(xy,x2-y2). In this framework, the electronic configuration is given by 1s(1/2)(2) 1p(3/2)(2) 1p(1/2)(2) 1d(5/2)(2) 1d(3/2)(2), which contribute to the analysis of the electronic structure of planar clusters in terms of spin-orbit coupling, involving molecular spinors (j = l +/- s) instead of molecular orbitals (pure l).