Dresden 2020 – wissenschaftliches Programm
Die DPG-Frühjahrstagung in Dresden musste abgesagt werden! Lesen Sie mehr ...
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
MM: Fachverband Metall- und Materialphysik
MM 49: Structural Materials (Steels, light-weight materials, high-temperature materials) - I
MM 49.5: Vortrag
Donnerstag, 19. März 2020, 11:15–11:30, BAR 205
CeMo2B5: a new type of arrangement of puckered boron hexagonal rings — •Sever Flipo1,2, Miroslav Kohout2, Friedrich Roth1, Tina Weigel1, Matej Bobnar2, Alim Ormeci1,2, Ulrich Burkhardt2, Christoph Hennig3, Tilmann Leisegang1, Dirk Carl Meyer1, Andreas Leithe-Jasper2, and Roman Gumeniuk1,2 — 1Institut für Experimentelle Physik, TU Bergakademie Freiberg, Leipziger Straße 23, 09596 Freiberg, Germany — 2Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Straße 40, 01187 Dresden, Germany — 3ESRF, 71, Avenue des Martyrs, Grenoble, France
REMo2B5 (RE = Ce, Pr, Nd) and CeW2B5 have been synthesized. CeMo2B5 crystallizes in a new structure type with space group Pnma, a = 11.0298(2) Å, b = 3.12080(5) Å, c = 9.9594(2) Å, Z = 4. Its structure reveals puckered [B6]-hexagonal rings, trigonal-prismatic- and empty slabs of condensed pyramids and tetrahedra. The structure can be related to the derivatives of AlB2 and CrB prototypes. The boron atoms form a two-dimensional network of corrugated ribbons, each composed of four edge-linked [B6] rings extending infinitely along the b-axis. The Chemical bonding scenario in CeMo2B5 is dominated by the chains of [Ce2Mo2] clusters with multi-center bond. These clusters are connected via metallic Mo*Mo bonds and the resulting framework is stabilized by bonding interactions with the boron ribbons to which it donates electrons. CeMo2B5 is a Pauli paramagnet and electrical transport measurements, as well as the calculated density of states at the Fermi level, show CeMo2B5 to be a typical metallic system.