Dresden 2017 – wissenschaftliches Programm
TT 19.28: Poster
Montag, 20. März 2017, 15:00–19:00, P2-EG
New 3d-5d double perovskites containing Ir5+ — •Klaus K. Wolff1, Martin Jansen2, Alexander C. Komarek1, and Liu Hao Tjeng1 — 1Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany — 2Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569 Stuttgart, Germany
Double perovskites with the general formula A2BB′O6 (A = alkaline-earth or rare earth metal, B = 3d transition metal, B′ = 4d or 5d transition metal) with an ordered rock-salt-like arrangement of corner-sharing alternating BO6 and B′O6 units are functional materials that have been extensively studied and are suitable for many applications, especially new magnets. For instance, Sr2FeMoO6 is a half-metallic ferromagnet (TC = 415 K) showing colossal magnetoresistance, and Sr2CrOsO6 exhibit ferrimagnetic ordering up to very high temperatures (TC = 725 K).
There are several representatives of double perovskites of the type A2BIrO6 (B = trivalent metal) containing Iridium in the formal oxidation state +5. The combination SrLaBB′O6 gives the possibility to combine divalent transition metal ions with Ir5+. By this approach, we were able to synthesize the new compounds SrLaNiIrO6 and SrLaCuIrO6. The first compound crystallizes monoclinically, whereas the second material presents higher tetragonal symmetry with significant Jahn-Teller distortion in the coordination sphere of the 3d9 ion Cu2+. Both compounds show isolating behavior. Electronic transport and magnetic data of the powder samples will be presented.