On the sensitivity of f electrons to their chemical environment.
Density functional calculations have been carried out on three families of lanthanide complexes of D3 or C4 symmetry, namely [Ln(H2O)9]3+, [Ln(DPA)3]3-, and [Ln(DOTAM)]3+ (Ln = Y, La, Lu; DPA = pyridine-2,6-dicarboxylate; DOTAM = 1,4,7,10-tetracarbamoylmethyl-1,4,7,10-tetraazacyclododecane), to get some insights concerning the sensitivity of 4f electrons to the surrounding ligands. We show that the electron density accumulations found within 0.7 A of the metal center, that precisely give the opposite image of the coordination sphere as they are located trans with respect to the Ln-ligand bonds, are almost exclusively due the f electrons. This polarization of the 4f electrons in lanthanides complexes has therefore to be considered as a general feature that plays a crucial role in some experimentally observed phenomenons such as the dependency of quadratic hyperpolarizability to the number of f electrons in [Ln(DPA)3]3- complexes that we have evidenced.
Furet
Eric
E
Sciences Chimiques de Rennes, UMR CNRS 6226 Ecole Nationale Supérieure de Chimie de Rennes Avenue du Général Leclerc, 35700 Rennes cedex, France. eric.furet@ensc-rennes.fr
Costuas
Karine
K
Rabiller
Philippe
P
Maury
Olivier
O
D004583:Electrons; D028581:Lanthanoid Series Elements / Q000737:chemistry*; D008958:Models, Molecular; D009942:Organometallic Compounds / Q000737:chemistry
D028581:Lanthanoid Series Elements; D009942:Organometallic Compounds