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arXiv · 2212.05593

Extracting the sample response function from experimental two-dimensional terahertz-infrared-visible spectra

Pankaj Seliya·Mischa Bonn·Maksim Grechko
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Abstract

Terahertz molecular motions are often probed by high-frequency molecular oscillators in different types of non-linear vibrational spectroscopy. Recently developed two-dimensional terahertz-infrared-visible spectroscopy allows direct measuring of this coupling and, thus, obtaining site-specific terahertz vibrational spectrum. However, these data are affected by the intensity and phase of the employed laser pulses. In this work, we develop a method of extracting sample response - representing solely physical properties of a material - from experimental spectra. Using dimethyl sulfoxide (DMSO) as a model molecule to verify this method, we measure the coupling between C-H stretch vibration of its methyl groups and terahertz intramolecular twist and wagging modes.

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Pankaj Seliya, Mischa Bonn, Maksim Grechko. 2022-12-11. Extracting the sample response function from experimental two-dimensional terahertz-infrared-visible spectra. https://doi.org/10.1063/5.0138442

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