Fakulta matematiky, fyziky
a informatiky
Univerzita Komenského v Bratislave

Seminár z fyziky tuhých látok - Mariana Derzsi (3.5.2019)

v piatok 3.5.2019 o 14:00 hod. v miestnosti F2/272


29. 04. 2019 14.39 hod.
Od: Richard Hlubina

Prednášajúci: Mariana Derzsi (Materiálovotechnologická fakulta STU, Trnava)

Názov: Theoretical quest for AgCl2 in solid state

Termín: 29.3.2019, 14:00 hod., F2/272


Abstrakt:

Dichlorides of late transition metals (MCl2) adopt diverse crystal geometries. One finds among them diamagnetic charge transfer insulators with typical ionic crystal structures (M=Zn, Cd), magnetically ordered semiconductors (Cu, Ni), unusual disproportionated M1+/M3+ forms (Au) as well as cluster (Pd, Pt) and even quasi-molecular considerably covalent forms (Hg). Yet, one stoichiometry at the very centre of the block is still missing: AgCl2. Its ‘nonexistence’ is not obvious – on one hand dichlorides of Cu and Au siblings are known, but on the other Ag2+ is a powerfully electron-withdrawing species, which could render Cl- unstable with respect to electron transfer reactions [1-3]. Based on the solid state DFT calculations we propose possible dynamically stable structures with unusual electronic structures [4] among metal chlorides.

[1] W. Grochala & R. Hoffmann, Angew. Chem. Int. Ed. 40, 2742 (2001).
[2] P. Malinowski et al., Z. Anorg. Allg. Chem. 634, 2608 (2008).
[3] M. Derzsi et al., Inorg. Chem. 49, 2735 (2010).
[4] J. Zaanen, G.A. Sawatzky & J.W. Allen, Phys. Rev. Lett. 55, 418 (1985).