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Updated: Jun 8, 2026

Measurement and Analysis of Atomic Hydrogen and Diatomic Molecular AlO, C2, CN, and TiO Spectra Following Laser-induced Optical Breakdown
Published on: February 14, 2014
[A study of vibrational spectra of L-, D-, DL-alanine in terahertz Domain]
Rong Fu1, Zhe Li, Biao-bing Jin
1Research Institute of Superconductor Electronics, Nanjing University, Nanjing 210093, China. woshifurong@hotmail.com
Abstract:
In the present paper the terahertz time-domain spectroscopy (THz-TDS) was used to measure the absorption spectra of L-, D-, DL-alpha-alanine at room temperature. A number of well-resolved absorption peaks were observed in the range of frequencies from 0.3 to 3.1 THz, which showed large differences in the spectra between the enantiomers (L-, D-alanine) and the racemic compound (DL-alanine). In parallel with the experimental study, the computed vibrational spectra were also obtained by using first principles calculations based on the density functional theory(DFT), which were in good agreement with the experimental data. Results show that the absorption spectra in terahertz region originate from the collective vibration based on hydrogen bonds.
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