Speaker: Prof. ian LIN (林念教授), The Hong Kong University of Science andTechnology

Host: Prof. Kai WU (吴凯教授)

Time: 15:00 p.m., August 28, 2023, GMT+8

Venue: College of Chemistry, Room CB215

Abstract:

In the first part of this talk. I will present the synthesis of four-. six- and eight-membered tetraphenylethylene (TPE)-based macrocycles on Ag(111) via on-surface Ullmann coupling reactions. Their unique chemical and physical properties, such as intrinsic inner cavities and aromaticity/antiaromaticity make these systems appealing building blocks for functional supramolecular materials. The as-synthesized macrocycles are spontaneously segregated on the surface and self-assemble as large-area two-dimensional mono-component supramolecular crystals. Combined in-situ characterized by scanning tunneling spectroscopic and computational analysis evidence that the macrocycles undergo structural and orbital symmetry breaking due to extended conjugation in the macrocvcles. In the second part I will show that TPE-based oligomers containing open-shell radicals represent a unique platform for exploring the quantum critical point in Kondo systems. The competition of inter-radical antiferromagnetic coupling and the Kondo screening leads to Kondo chains. which offers opportunities to realize artificial heavy fermion systems using organic radicals.

Source: College of Chemistry and Molecular Engineering