Application of a planar superatom model on [Hg5(C(CF3)2)]. Bonding and magnetic response considerations into a five-fold d10–d10 metal cycle

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 d¹⁰–d¹⁰ 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 1s² 1p⁴_x,y 1d⁴_xy,x²−y². The analysis of the population of each level of the Hg₅core, 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 d¹⁰ macrocyclic clusters with metallophilic interactions, in the category of long d¹⁰–d¹⁰ 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 ≠ 0, namely, 1p_x,y and 1d_xy,x²−y². In this framework, the electronic configuration is given by 1s_1/2² 1p_3/2² 1p_1/2² 1d_5/2² 1d_3/2², which contribute to the analysis of the electronic structure of planar clusters in terms of spin–orbit coupling, involving molecular spinors (j = ± s) instead of molecular orbitals (pure ).