A density functional investigation on d0-Zr(IV) organometallic fragments

The density functional approach has been used to compare the geometry and the frontier orbitals of the [(COT)Zr]2+, [CpZr]3+, [Cp2Zr]2+ and [calix[4]–(O)4Zr] fragments. The investigation on the [(COT)Zr]2+ and [Cp2Zr]2+ complexes shows that, in spite of the same number of low-lying empty orbitals available for bonding with additional ligands, the symmetries and the spatial extensions of these orbitals are different, and this has important consequences on their chemical behavior.