Research on Electronically Forbidden Raman Pathways in Single-Molecule TERS by Assistant Professor Mamoru Tamura of School of Science is Published in Nano Letters

On March 16, 2026, the results of research by Hiroyuki Ikagawa (doctoral student at the time), Department of Materials Engineering Science, The University of Osaka, Assistant Professor Mamoru Tamura, School of Science, Kwansei Gakuin University, and Professor Hajime Ishihara, Research Organization of Science and Technology, Ritsumeikan University, on electronically forbidden Raman pathways in single-molecule TERS were published in Nano Letters.

The research demonstrated that by developing a resonance Raman theory explicitly incorporating the multipolar structure of electronic states, electronically forbidden Raman pathways become activated under electronic resonance conditions, allowing differences between vibrational modes that are experimentally difficult to distinguish to manifest as distinct spatial patterns in single-molecule TERS images. These findings are expected to provide new theoretical guidelines for the precise characterization of electronic and vibrational states in functional organic molecules and low-dimensional material systems, contributing to future advances in molecular measurement and materials analysis.

Journal name: Nano Letters
Article title: Electronically Forbidden Raman Pathways Create a New Contrast Mechanism in Single-Molecule TERS
Authors: Hiroyuki Ikagawa, Mamoru Tamura*, and Hajime Ishihara*
DOI: 10.1021/acs.nanolett.5c06490