title: Extending the Row of Lanthanide Tetrafluorides: A Combined Matrix-Isolation and Quantum-Chemical Study.
abstract: Only the neutral tetrafluorides of Ce, Pr, and Tb as well as the [LnF7 ](3-) anions of Dy and Nd, with the metal in the +IV oxidation state, have been previously reported. We report our attempts to extend the row of neutral lanthanide tetrafluorides through the reaction of laser-ablated metal atoms with fluorine and their stabilization and characterization by matrix-isolation IR spectroscopy. In addition to the above three tetrafluorides, we found two new tetrafluorides, (3) NdF4 and (7) DyF4 , both of which are in the +IV oxidation state, which extends this lanthanide oxidation state to two new metals. Our experimental results are supported by quantum-chemical calculations and the role of the lanthanide oxidation state is discussed for both the LnF4 and [LnF4 ](-) species. Most of the LnF4 species are predicted to be in the +IV oxidation state and all of the [LnF4 ](-) anions are predicted to be in the +III oxidation state. The LnF4 species are predicted to be strong oxidizing agents and the LnF3 species are predicted to be moderate to strong Lewis acids.
authors.affiliation: Albert-Ludwigs-Universität Freiburg, Institut für Anorganische und Analytische Chemie, Albertstrasse 21, 79104, Freiburg, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Vent-Schmidt
authors.affiliation: Department of Chemistry, The University of Alabama, Tuscaloosa, Alabama, 35487-0336, USA.
authors.forename: Zongtang
authors.initials: Z
authors.lastname: Fang
authors.affiliation: Department of Chemistry, The University of Alabama, Tuscaloosa, Alabama, 35487-0336, USA.
authors.forename: Zachary
authors.initials: Z
authors.lastname: Lee
authors.affiliation: Department of Chemistry, The University of Alabama, Tuscaloosa, Alabama, 35487-0336, USA. dadixon@bama.ua.edu.
authors.forename: David
authors.initials: D
authors.lastname: Dixon
authors.affiliation: Freie Universität Berlin, Institut für Chemie und Biochemie, Fabeckstrasse 34-36, 14195, Berlin, Germany. sriedel@fu-berlin.de.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Riedel
keywords: electronic structure; fluorine; high oxidation states; lanthanides; matrix-isolation