Comparison of chain versus sheet crystal structures for the cyanidesMCN(M=CuAu)and dicarbidesMC2(M=BeBa,ZnHg)

2007/01/26 by P. Zaleski-Ejgierd, Patryk Zaleski‐Ejgierd, Mikko Hakala +3
Chemistry · Physics and Astronomy · #Inorganic Chemistry and Materials #Inorganic Fluorides and Related Compounds #Synthesis and characterization of novel inorganic/organometallic compounds #cond-mat.mtrl-sci

paper · pdf · doi:10.1103/physrevb.76.094104

8 pages, 8 figures, 10 tables

arxiv created 2007/01/26 · openalex publication_date 2007/09/10 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28

Abstract

The cyanides MCN, M=Cu,Ag,Au, have experimentally a structure with hexagonally packed, infinite MCNMCN chains. Following our earlier study for AuCN, we now predict that all three MCN could have an alternative M₃C₃N₃ sheet structure of comparable energy with the known one. The valence isoelectronic systems MC₂ versus M₃C₆, M=BeBa,ZnHg, are also studied. Now, the known dicarbides have the CaC₂ or MgC₂ chain structures, which are well reproduced. The predicted sheets lie energetically below the chains for M=Zn, Cd, and Hg. All these group-12 systems are experimentally unknown. Indeed, they are clearly endothermic, compared to the elements. For some sheet structures, the densities of states suggest rather small band gaps and even metallic character. When available, the experimental geometries agree well with the calculated ones.

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