Cooperative Binding of 1-Phenylimidazole to Cobalt(II) Octaethylporphyrin on Graphite: A Quantitative Imaging and Computational Study at Molecular Resolution
Cooperative Binding of 1-Phenylimidazole to Cobalt(II) Octaethylporphyrin on Graphite: A Quantitative Imaging and Computational Study at Molecular Resolution
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DOI：
10.1021/acs.jpcc.0c05516
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发表时间：
2020-08-27
影响因子：
3.7
通讯作者：
Mazur, Ursula
中科院分区：
文献类型：
--
作者：
Korpany, Katalin, V;Chilukuri, Bhaskar;Mazur, Ursula
协同相互作用在生物系统的稳定性和反应性中起着至关重要的作用，并且在功能材料的合成中越来越重要，但这种现象的定量单分子测量很少。许多这些合作的相互作用必然发生在表面上，使合作的界面上的影响的研究特别重要。在这里，我们报告了1-苯基咪唑（PhIm）的合作结合的定量实验和理论研究钴（II）八乙基卟啉（CoOEP）的高取向热解石墨（HOPG）在溶液-固体界面。扫描隧道显微镜（STM）以单分子分辨率证实并监测PhIm与HOPG支持的CoOEP的结合。这些STM图像的最近邻分析显示积极的合作结合行为。PhIm/CoOEP/HOPG和钴（II）卟啉（CoP）/HOPG体系的周期性平面波密度泛函理论（DFT）计算支持正协同性的实验观察。密度泛函理论计算表明，PhIm与Co-卟啉的结合能随着PhIm与更多相邻分子的结合而增加.计算还表明，HOPG的存在是至关重要的，在这个系统中观察到积极的协同性。
Cooperative interactions play a critical role in the stability and reactivity of biological systems and are an increasingly important consideration in the synthesis of functional materials, but quantitative single-molecule measurements of this phenomenon are rare. Many of these cooperative interactions necessarily occur on surfaces, making the study of cooperative effects at interfaces of particular importance. Here, we report a quantitative experimental and theoretical study of the cooperative binding of 1-phenylimidazole (PhIm) to cobalt(II) octaethylporphyrin (CoOEP) on highly oriented pyrolytic graphite (HOPG) at the solution-solid interface. Scanning tunneling microscopy (STM) confirmed and monitored the binding of PhIm to HOPG- supported CoOEP with single-molecule resolution. Nearest-neighbor analysis of these STM images revealed positive cooperative binding behavior. Periodic plane-wave density functional theory (DFT) calculations of PhIm/CoOEP/HOPG and cobalt(II) porphine (CoP)/HOPG systems support the experimental observations of positive cooperativity. DFT calculations revealed that the binding energy of PhIm to Co-porphyrin increases as PhIm binds to more neighboring molecules. Calculations also suggest that the presence of HOPG is crucial to observe positive cooperativity in this system.