Architecture of Heptagonal Metallo-macrocycles via Embedding Metal Nodes Into Its Rigid Backbone

Presenter and Co-Authors

A.M.Shashika D. Wijerathna, Department of Physics, Old Dominion University, Norfolk, Virginia 23529, United StatesFollow
He Zhao, Department of Organic and Polymer Chemistry; Hunan Key Laboratory of Micro Nano Materials Interface Science, College of Chemistry and Chemical Engineering; Central South University, Changsha, Hunan-410083, China
Qiangqiang Dong, Department of Organic and Polymer Chemistry; Hunan Key Laboratory of Micro Nano Materials Interface Science, College of Chemistry and Chemical Engineering; Central South University, Changsha, Hunan-410083, China
Qixia Bai, Institute of Environmental Research at Greater Bay Area; Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education; Guangzhou Key Laboratory for Clean Energy and Materials, Guangzhou University, Guangzhou-510006, China
Zhiyuan Jiang, Department of Organic and Polymer Chemistry; Hunan Key Laboratory of Micro Nano Materials Interface Science, College of Chemistry and Chemical Engineering; Central South University, Changsha, Hunan-410083, China
Jie Yuan, School of Chemistry and Chemical Engineering, Henan Normal University Xinxiang, Henan 453007,China
Jun Wang, Institute of Environmental Research at Greater Bay Area; Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education; Guangzhou Key Laboratory for Clean Energy and Materials, Guangzhou University, Guangzhou-510006, China
Mingzhao Chen, Institute of Environmental Research at Greater Bay Area; Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education; Guangzhou Key Laboratory for Clean Energy and Materials, Guangzhou University, Guangzhou-510006, China
Markus Zirnheld, Department of Physics, Old Dominion University, Norfolk, Virginia 23529, United StatesFollow
Rockwell T. Li, Math and Science Academy at Ocean Lakes High School, Virginia Beach, Virginia, 23454, United State
Yuan Zhang, Department of Physics, Old Dominion University, Norfolk, Virginia 23529, United StatesFollow
Yiming Li, Department of Organic and Polymer Chemistry; Hunan Key Laboratory of Micro Nano Materials Interface Science, College of Chemistry and Chemical Engineering; Central South University, Changsha, Hunan-410083, China
Pingshan Wang, Department of Organic and Polymer Chemistry; Hunan Key Laboratory of Micro Nano Materials Interface Science, College of Chemistry and Chemical Engineering; Central South University, Changsha, Hunan-410083, China and Institute of Environmental Research at Greater Bay Area; Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education; Guangzhou Key Laboratory for Clean Energy and Materials, Guangzhou University, Guangzhou-510006, China

ORCID

0000-0002-6003-6801 (Wijerathna), 0000-0002-7431-5262 (Zhang)

College

College of Sciences

Department

Physics

Graduate Level

Doctoral

Publication Date

2023

DOI

10.25883/1hce-pr68

Abstract

Metal-organic macrocycles have received increasing attention not only due to their versatile applications such as molecular recognition, compounds encapsulation, anti-bacteria and others, but also for their important role in the study of structure-property relationship at nano scale. However, most of the constructions utilize benzene ring as the backbone, which restricts the ligand arm angle in the range of 60, 120 and 180 degrees. Thus, the topologies of most metallo-macrocycles are limited as triangles and hexagons, and explorations of using other backbones with large angles and the construction of metallo-macrocycles with more than six edges are very rare.

In this study, we present a novel strategy for self-assembly two giant heptagonal metallo-macrocycles with an inner diameter of 5 nm, by embedding metal nodes into the ligand backbone and regulating the ligand arm angle. By complexing with metal ions, the angle between two arms at the 4,4” position of the central terpyridine (tpy) was extended, resulting in ring expansion of the metallo-macrocycle. This approach enabled the construction of giant and more complex metallo- macrocycles that could not be achieved with traditional benzene ring backbones. The characterization of complex molecules often requires the use of multiple techniques, such as multi-dimensional and multinuclear NMR and multidimensional mass spectrometry analysis. Here, we also utilized transmission electron microscopy (TEM) and ultra-high vacuum (∼E-10 torr) low-temperature (∼77 K) scanning tunneling microscopy (UHV-LT-STM) to characterize complex supramolecules. The resulting metallo-macrocycles formed hierarchical self-assembled nanotube structures at larger densities, which is observed by TEM, while UHV-LT-STM was used for direct visualization of individual complex supramolecules deposited on an Au(111) substrate. Our findings indicate that UHV-LT-STM is an effective methodology for characterizing supramolecules at a single molecule level, providing more details of the molecular structure that is difficult to resolve by the resolution of TEM.

Keywords

Self-assembly, Terpyridine, Concentric heptagonal metallo-macrocycle, Metal coordination node, Scanning tunneling microscope, Supramolecule characterization

Disciplines

Condensed Matter Physics | Nanoscience and Nanotechnology | Organic Chemistry | Quantum Physics | Structural Materials

Files

Recommended Citation

Wijerathna, A.M.Shashika D.; Zhao, He; Dong, Qiangqiang; Bai, Qixia; Jiang, Zhiyuan; Yuan, Jie; Wang, Jun; Chen, Mingzhao; Zirnheld, Markus; Li, Rockwell T.; Zhang, Yuan; Li, Yiming; and Wang, Pingshan, "Architecture of Heptagonal Metallo-macrocycles via Embedding Metal Nodes Into Its Rigid Backbone" (2023). College of Sciences Posters. 12.
https://digitalcommons.odu.edu/gradposters2023_sciences/12