Crystal structure and physical properties of the new silicide Hf4CuSi4 with planar CuSi4 rectanglesElectronic supplementary information (ESI) available: Figure displaying densities of states (left) and selected cumulated COHP curves of Y4GaCo4. CCDC reference number 762386. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c0jm00066c

• Main Authors: Guch, Mykhailo, Assoud, Abdeljalil, Kleinke, Holger
• Format: Article
• Language: English
• ISSN: 0959-9428; 1364-5501
• DOI: 10.1039/c0jm00066c

The new compound Hf 4 CuSi 4 was prepared via a high-temperature reaction in a resistance furnace. Hf 4 CuSi 4 adopts the Y 4 GaCo 4 structure type in the space group C 2/ m , with cell dimensions of a = 9.6945(8) Å, b = 3.7498(3) Å, c = 8.6531(7) Å, β = 109.912(1)° and V = 295.76(4) Å 3 . Parts of its structure are reminiscent of HfSi, e.g. its six-membered Hf-channels running along the [100] direction. The hexagonal channels are interconnected via Hf-Hf bonds to a three-dimensional network of Hf atoms. Each channel contains CuSi 4/2 strips interconnected via Si atoms to form infinite layers. The Cu atoms are coordinated by four Si atoms in form of a planar rectangle. This material is metallic with a distinct pseudo-gap at 0.45 eV above the Fermi level. Hf 4 CuSi 4 contains planar CuSi 4 rectangles interconnected to chains and via Si 4 10− zigzag chains to infinite puckered layers. The material is metallic, exhibiting a distinct pseudo-band gap at 0.45 eV above the Fermi level.