Gas-Phase Structures of Potassium Tetrakis(hexafluoro- acetylacetonato) Lanthanide(III) Complexes [KLn(C₅ HF₆ O₂ )₄ ] (Ln=La, Gd, Lu).

ABSTRACT: The molecular structures of potassium tetrakis(hexafluoroacetylacetonato)lanthanide(III) complexes [KLn(hfa)₄ ] (Ln=La, Gd, Lu; hfa=C₅ HF₆ O₂ ,) were studied by synchronous gas-phase electron diffraction/mass spectrometry (GED/MS) supported by quantum-chemical (DFT/PBE0) calculations. The compounds sublime congruently and the vapors contain a single molecular species: the heterobinuclear complex [KLn(hfa)₄ ]. All molecules are of C₁ symmetry with the lanthanide atom in the center of an LnO₈ coordination polyhedron, while the potassium atom is coordinated by three ligands with formation of three K-O and three K-F bonds. One hfa ligand is not bonded to the potassium atom. Topological analysis of the electron-density distributions confirmed the existence of ionic-type K-O and K-F bonding. The structures of the free [KLn(hfa)₄ ] molecules are compared with those of the related compounds [KDy(hfa)₄ ] and [KEr(hfa)₄ ] in their crystalline state. The complex nature of the chemical bonding is discussed on the basis of electron-density topology analyses.

SUBMITTER: Girichev GV 

PROVIDER: S-EPMC7839460 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature