title: Exploring the nature of the excitation energies in [Re6(μ3-Q8)X6](4-) clusters: a relativistic approach.
abstract: This contribution is a relativistic theoretical study to characterize systematically the main electronic transitions in a series of hexarhenium chalcogenide [Re6(μ3-Q8)X6](4-) clusters with the aim of understanding: (i) the terminal ligand substitution effect, (ii) the substitution effect of the chalcogenide ion on the [Re6(μ3-Q8)](2+)core, and finally (iii) the significance of the spin-orbit coupling (SOC) effect on the optical selection rules. In all the cases, we found characteristic bands at around 300-550 nm, where the band positions are directly determined by the terminal ligand. However, SCN(-)/NCS(-) presents a different nature of the orbitals involved in the electronic transitions, in comparison with the other studied terminal ligands, located in the near-infrared (NIR) region. All the bands are red-shifted as a consequence of the ligand contribution in the composition of the orbitals involved in the electronic excitations.
authors.affiliation: Universidad Andrés Bello, Facultad de Ciencias Exactas, PhD Program in Molecular Physical Chemistry, Relativistic Molecular Physics (ReMoPhys) Group, Santiago, Chile. rarratia@unab.cl.
authors.forename: Walter A
authors.initials: WA
authors.lastname: Rabanal-León
authors.forename: Juliana A
authors.initials: JA
authors.lastname: Murillo-López
authors.forename: Dayán
authors.initials: D
authors.lastname: Páez-Hernández
authors.forename: Ramiro
authors.initials: R
authors.lastname: Arratia-Pérez