Center for Soft Nanoscience (SoN), Westfälische Wilhelms-Universität Münster, Münster, Germany.
Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA, USA.
Chirality. 2021 Feb;33(2):93-102. doi: 10.1002/chir.23290. Epub 2021 Jan 5.
Monolayers of chiral molecules can preferentially transmit electrons with a specific spin orientation, introducing chiral molecules as efficient spin filters. This phenomenon is established as chirality-induced spin selectivity (CISS) and was demonstrated directly for the first time in self-assembled monolayers (SAMs) of double-stranded DNA (dsDNA) . Here, we discuss SAMs of double-stranded peptide nucleic acid (dsPNA) as a system which allows for systematic investigations of the influence of various molecular properties on CISS. In photoemission studies, SAMs of chiral, γ-modified PNA show significant spin filtering of up to P = (24.4 ± 4.3)% spin polarization. The polarization values found in PNA lacking chiral monomers are considerably lower at about P = 12%. The results confirm that the preferred spin orientation is directly linked to the molecular handedness and indicate that the spin filtering capacity of the dsPNA helices might be enhanced by introduction of chiral centers in the constituting peptide monomers.
手性分子的单层可以优先传输具有特定自旋取向的电子，从而将手性分子引入为有效的自旋过滤器。这种现象被确立为手性诱导自旋选择性（CISS），并首次在双链 DNA（dsDNA）的自组装单层（SAM）中直接证明。在这里，我们讨论了双链肽核酸（dsPNA）的 SAM 作为一个系统，该系统允许对手性诱导自旋选择性的影响进行各种分子性质的系统研究。在光电子研究中，手性γ修饰的 PNA 的 SAM 表现出高达 P =（24.4±4.3）％的自旋极化的显著自旋过滤。在没有手性单体的 PNA 中发现的极化值要低得多，约为 P = 12％。结果证实，优先的自旋取向与分子手性直接相关，并表明构成 dsPNA 螺旋的自旋过滤能力可以通过在组成肽单体中引入手性中心来增强。
