TY - JOUR
T1 - Structural characteristics of mixed nido-[Si9−xGex]4− (x=1, 2) Zintl clusters in solution and within solvent crystals
AU - Jantke, Laura-Alice
AU - Karttunen, Antti J.
AU - Fässler, Thomas F.
N1 - Funding Information:
A. J. K. gratefully acknowledges computing time from CSC – the Finnish IT Center for Science and T.F.F. funding through the project “Solar Technologies go Hybrid” (Bavarian State Ministry for Science and the Arts). Open Access funding enabled and organized by Projekt DEAL.
PY - 2023/2/1
Y1 - 2023/2/1
N2 - Mixed Zintl-type anionic clusters of silicon and germanium comprise an important class of potential materials in electronic applications. Herein, we present quantum chemical investigations to describe the mixing behavior of Si and Ge within [Si9−xGex]4− (x=0, 1, 2) Zintl anions that can be considered as precursors for novel Si−Ge materials. To understand the mixing behavior of such clusters in solution, we analyze the molecular clusters at using Density Functional Theory (DFT) and Coupled Cluster methods. Systematic assessment of relative energies of various structural isomers indicates that there is a preference to substitute Si with Ge in the open square of the monocapped square antiprismatic [Si8Ge]4− and [Si7Ge2]4− clusters. Population analysis reveals that the highest negative partial charge is also located at these positions. Investigation of Rb4Si9−xGex(NH3)5 solvent crystals using DFT methods and periodic boundary conditions further elucidates the behavior during crystallization. It is shown that in addition to the favored [Si8Ge]4− open-square isomers arising in solution, the weak intermolecular interactions in the crystalline environment affect which structural isomers are observed in the crystal structure. The experimentally observed Ge site occupations could be explained by analysis of their energetics. This analysis contributes to the understanding of the mixing behavior of these important building blocks for material design.
AB - Mixed Zintl-type anionic clusters of silicon and germanium comprise an important class of potential materials in electronic applications. Herein, we present quantum chemical investigations to describe the mixing behavior of Si and Ge within [Si9−xGex]4− (x=0, 1, 2) Zintl anions that can be considered as precursors for novel Si−Ge materials. To understand the mixing behavior of such clusters in solution, we analyze the molecular clusters at using Density Functional Theory (DFT) and Coupled Cluster methods. Systematic assessment of relative energies of various structural isomers indicates that there is a preference to substitute Si with Ge in the open square of the monocapped square antiprismatic [Si8Ge]4− and [Si7Ge2]4− clusters. Population analysis reveals that the highest negative partial charge is also located at these positions. Investigation of Rb4Si9−xGex(NH3)5 solvent crystals using DFT methods and periodic boundary conditions further elucidates the behavior during crystallization. It is shown that in addition to the favored [Si8Ge]4− open-square isomers arising in solution, the weak intermolecular interactions in the crystalline environment affect which structural isomers are observed in the crystal structure. The experimentally observed Ge site occupations could be explained by analysis of their energetics. This analysis contributes to the understanding of the mixing behavior of these important building blocks for material design.
UR - http://www.scopus.com/inward/record.url?scp=85143278949&partnerID=8YFLogxK
U2 - 10.1002/zaac.202200276
DO - 10.1002/zaac.202200276
M3 - Article
AN - SCOPUS:85143278949
SN - 0044-2313
VL - 649
JO - Zeitschrift fur Anorganische und Allgemeine Chemie
JF - Zeitschrift fur Anorganische und Allgemeine Chemie
IS - 3
M1 - e202200276
ER -