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Updated: Jul 19, 2025

Raman and IR Spectroelectrochemical Methods as Tools to Analyze Conjugated Organic Compounds
Published on: October 12, 2018
Localized vibrational characteristics of biphenylene strips resulting in length-dependent Raman spectra
Yirui Lu1, Lei Yan1, Sichen Huang1
1School of physics and information technology, Shaanxi Normal University, Shaanxi, Xi'an 710119, China. yanlei@snnu.edu.cn.
Abstract:
The length dependence of the Raman spectra and vibrational properties of biphenylene strips are explored using density functional theory. The Raman intensity of two bands increases and decreases with length due to the enlarging and shrinking of the proportion of effective vibrating units. The red shift of vibrational modes is observed with the increase in length, owing to the various vibrational characteristics of the effective vibrating units. More importantly, a linear relationship between the energy gap and the wavenumber of the shifting Raman bands is obtained. The results allow us to interpret the length-dependence of the Raman spectra from the perspective of localized vibrational characteristics and suggest that Raman spectroscopy can be used as a convenient method to determine the energy gap of nanomaterials.
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