Baumgartner Maximilian, Weihrich Richard, Nilges Tom
Department of Chemistry, Technical University of Munich, Lichtenbergstr. 4, 85747, Garching, Germany.
Institute for Materials Resource Management, University of Augsburg, Universitätsstr. 1, 86135, Augsburg, Germany.
Chemistry. 2017 May 5;23(26):6452-6457. doi: 10.1002/chem.201700929. Epub 2017 Apr 7.
Inspired by the synthesis of the first atomic-scale double-helix semiconductor SnIP, this study deals with the question of whether more atomistic, inorganic double-helix compounds are accessible. With the aid of quantum chemical calculations, we have identified 31 candidates by a homoatomic substitution in MXPn, varying the Group 14 M-element from Si to Pb, the Group 17 X-element from F to I and replacing the pnictide (Pn) phosphorus by arsenic. The double-helical structure of SnIP has been used as the starting model for all candidates and the electronic structure and vibrational spectra were determined within the framework of density functional theory (DFT). Varying the outer MX or the inner Pn helix led to the conclusion that iodide- and bromide-containing MXPn compounds show similar structures to SnIP. Here, the calculations indicate interesting effects for electronic band-gap tuning. For the highly polarized fluorides, a segregation of the helices to more complex MX substructures is predicted.
受首个原子尺度双螺旋半导体SnIP合成的启发，本研究探讨了是否可以获得更多原子级的无机双螺旋化合物这一问题。借助量子化学计算，我们通过在MXPn中进行同原子取代确定了31种候选物，将第14族M元素从Si变化到Pb，第17族X元素从F变化到I，并将磷族元素（Pn）磷替换为砷。SnIP的双螺旋结构已用作所有候选物的起始模型，并在密度泛函理论（DFT）框架内确定了电子结构和振动光谱。改变外部MX或内部Pn螺旋得出结论，含碘化物和溴化物的MXPn化合物显示出与SnIP相似的结构。在此，计算表明了对电子带隙调谐的有趣影响。对于高度极化的氟化物，预计螺旋体会分离为更复杂的MX子结构。
