title: The Jahn-Teller effect: a case of incomplete theory for d4 complexes?
abstract: We present relativistic calculations at the four-component Dirac-DFT level for the geometries of the series of group 9 monoanionic hexafluorides MF(6)(-), M = Co, Rh, Ir. Highly correlated four-component relativistic CCSD(T) energies were also calculated for the optimized geometries. Spin-orbit coupling effects influence the geometrical preferences for molecular structures: relativistic calculations predict ground states with octahedral symmetries O(h)* for all hexafluorides in this study, while at the nonrelativistic limit, a structural deviation toward D(4h) ground state symmetries is predicted. Our findings suggest that relativistic effects have an important role in molecular structure preferences for the title hexafluorides.
authors.affiliation: Escuela de Ciencias y Humanidades, Departamento de Ciencias básicas, Universidad Eafit AA 3300, Medellín, Colombia.
authors.forename: Jorge
authors.initials: J
authors.lastname: David
authors.forename: Doris
authors.initials: D
authors.lastname: Guerra
authors.forename: Albeiro
authors.initials: A
authors.lastname: Restrepo