Department of Chemistry, University of Eastern Finland, P.O. Box 111, FI-80101 Joensuu, Finland.
Chemphyschem. 2010 Jun 21;11(9):1944-50. doi: 10.1002/cphc.200900987.
We investigated the structural principles of novel germanium modifications derived by oxidative coupling of Zintl-type Ge(9)clusters in various ways. The structures, stabilities, and electronic properties of the predicted {(2) (infinity)Ge(9)} sheet, {(1) (infinity)Ge(9)} nanotubes, and fullerene-like {Ge(9)}(n) cages were studied by using quantum chemical methods. The polyhedral {Ge(9)}(n) cages are energetically comparable with bulk-like nanostructures of the same size, in good agreement with previous experimental findings. Three-dimensional structures derived from the structures of lower dimensionality are expected to shed light on the structural characteristics of the existing mesoporous Ge materials that possess promising optoelectronic properties. Furthermore, 3D networks derived from the polyhedral {Ge(9)}(n) cages lead to structures that are closely related to the well-known LTA zeolite framework, suggesting further possibilities for deriving novel mesoporous modifications of germanium. Raman and IR spectra and simulated X-ray diffraction patterns of the predicted materials are given to facilitate comparisons with experimental results. The studied novel germanium modifications are semiconducting, and several structure types possess noticeably larger band gaps than bulk alpha-Ge.
我们以各种方式研究了通过 Zintl 型 [Ge(9)]4- 簇的氧化偶联衍生的新型锗修饰的结构原理。通过量子化学方法研究了预测的 {(2) (infinity)[Ge(9)] (n)} 片、{(1) (infinity)[Ge(9)] (n)} 纳米管和类富勒烯 {Ge(9)} (n) 笼的结构、稳定性和电子性质。多面体 {Ge(9)} (n) 笼与相同尺寸的块状纳米结构在能量上具有可比性，这与先前的实验结果一致。预计从低维结构衍生的三维结构将揭示具有有前途的光电性能的现有介孔 Ge 材料的结构特征。此外，多面体 {Ge(9)} (n) 笼衍生的 3D 网络导致与众所周知的 LTA 沸石骨架密切相关的结构，这表明进一步衍生新型介孔锗修饰的可能性。给出了预测材料的 Raman 和 IR 光谱以及模拟 X 射线衍射图谱，以方便与实验结果进行比较。所研究的新型锗修饰是半导体，几种结构类型的带隙明显大于块状 α-Ge。
