Structural Parameters and Electron Transfer in Ytterbium, Lutetium, and Cerium Compounds with Hydrocarbon Monocycles

The DFT (U)PBE0 method was used to calculate the structural parameters of the C5H5Yb·, C5H5Lu, C8H8Lu·, C8H8Yb, (C5H5)2Yb, (C5H5)3Yb, C5H5YbC8H8, C5H5Ce·C8H8, C5H5LuC8H8, (C8H8)2Lu, (C8H8)Ce*, (C8H8)2Ce, (C8H8LuC8H8)2Yb, and (C8H8Ce·C8H8)2Yb molecules. In the (C8H8)2Ce molecule, the oxidation state of the lanthanide is higher than in the quadruple-decker (C8H8LnC8H8)2Yb complexes, in the C5H5LnC8H8 molecules, and in the free radicals (C8H8)2Ce* and (C8H8)2Lu. Oxidation of (C5H5)2Yb with cyclooctatetraene and the binding of the (C8H8)2Ln molecules by ytterbium(II) are exothermic reactions. The atomic charges and the dipole and quadrupole moments are indicative of incomplete transfer of the lanthanide valence electrons to the ligands, i.e., of a significant covalent component of the η5 and η8 bonds. Lutetium interacts with cyclooctatetraene as a lanthanide, without showing the properties of transition metals.