title: A terahertz study of taurine: Dispersion correction and mode couplings.
abstract: The low-frequency characteristics of polycrystalline taurine were studied experimentally by terahertz (THz) absorption spectroscopy and theoretically by ab initio density-functional simulations. Full optimizations with semi-empirical dispersion correction were performed in spectral computations and vibrational mode assignments. For comparison, partial optimizations with pure density functional theory were conducted in parallel. Results indicate that adding long-range dispersion correction to the standard DFT better reproduces the measured THz spectra than the popular partial optimizations. The main origins of the observed absorption features were also identified. Moreover, a coupled-oscillators model was proposed to explain the experimental observation of the unusual spectralblue-shift with the increase of temperature. Such coupled-oscillators model not only provides insights into the temperature dynamics of non-bonded interactions but also offers an opportunity to better understand the physical mechanisms behind the unusual THz spectral behaviors in taurine. Particularly, the simulation approach and novel coupled-oscillators model presented in this work are applicable to analyze the THz spectra of other molecular systems.
authors.affiliation: State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054, People's Republic of China.
authors.forename: Zelin
authors.initials: Z
authors.lastname: Dai
authors.affiliation: State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054, People's Republic of China.
authors.forename: Xiangdong
authors.identifier: 0000000227785464
authors.initials: X
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054, People's Republic of China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Gu
authors.affiliation: State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054, People's Republic of China.
authors.forename: Xinrong
authors.initials: X
authors.lastname: Li
authors.affiliation: State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054, People's Republic of China.
authors.forename: Fu
authors.initials: F
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054, People's Republic of China.
authors.forename: Yuxiang
authors.initials: Y
authors.lastname: Lian
authors.affiliation: State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054, People's Republic of China.
authors.forename: Kai
authors.identifier: 0000000196288210
authors.initials: K
authors.lastname: Fan
authors.affiliation: State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054, People's Republic of China.
authors.forename: Xiaomeng
authors.initials: X
authors.lastname: Cheng
authors.affiliation: State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054, People's Republic of China.
authors.forename: Zhegeng
authors.initials: Z
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054, People's Republic of China.
authors.forename: Minghui
authors.initials: M
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054, People's Republic of China.
authors.forename: Yadong
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: College of Chemistry and Material Science, Sichuan Normal University, Chengdu 610068, People's Republic of China.
authors.forename: Chun
authors.initials: C
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054, People's Republic of China.
authors.forename: Jimmy
authors.initials: J
authors.lastname: Xu