Differential Charging in Photoemission from Mercurated DNA Monolayers on Ferromagnetic Films.
Differential Charging in Photoemission from Mercurated DNA Monolayers on Ferromagnetic Films.
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DOI：
10.1021/acs.nanolett.9b04622
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发表时间：
2020-01
期刊：
影响因子：
10.8
通讯作者：
D. Stemer;J. Abendroth;Kevin M. Cheung;Matthew Ye;M. E. El Hadri;E. Fullerton;P. Weiss
中科院分区：
文献类型：
--
作者：
D. Stemer;J. Abendroth;Kevin M. Cheung;Matthew Ye;M. E. El Hadri;E. Fullerton;P. Weiss
光电子在手性分子膜中的传输存在自旋相关和对映选择性的电子-分子散射。这种自旋选择性导致电子自旋过滤分子螺旋，随着幅度的增加，伴随着螺旋圈数的增加。使用紫外光电子能谱，我们测量了自旋选择性表面充电伴随的光电子发射功能化与单层的汞化DNA发夹，构成只有一个螺旋圈的铁磁基板。汞离子特异性地结合在自杂交的单链DNA内的胸腺嘧啶-胸腺嘧啶错配处，使得能够精确控制Hg 2+沿着螺旋轴的数量和位置。差分充电的有机层，表现为基板的磁化依赖的光电离能，观察到的DNA发夹含有汞2 +;没有差异，测量发夹单层在没有汞2+。反转的DNA螺旋二级结构在增加金属负载导致互补反转的自旋选择性。我们将这些结果归因于汞化DNA中自旋-轨道相互作用的相对论增强导致的散射概率增加。
Spin-dependent and enantioselective electron-molecule scattering occurs in photoelectron transmission through chiral molecular films. This spin selectivity leads to electron spin filtering by molecular helices, with increasing magnitude, concomitant with increasing numbers of helical turns. Using ultraviolet photoelectron spectroscopy, we measured spin-selective surface charging accompanying photoemission from ferromagnetic substrates functionalized with monolayers of mercurated DNA hairpins that constitute only one helical turn. Mercury ions bind specifically at thymine-thymine mismatches within self-hybridized single-stranded DNA, enabling precise control over the number and position of Hg2+ along the helical axis. Differential charging of the organic layers, manifested as substrate magnetization-dependent photoionization energies, was observed for DNA hairpins containing Hg2+; no differences were measured for hairpin monolayers in the absence of Hg2+. Inversion of the DNA helical secondary structure at increased metal loading led to complementary inversion in spin selectivity. We attribute these results to increased scattering probabilities from relativistic enhancement of spin-orbit interactions in mercurated DNA.