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Li F.,State Key Laboratory of Superhard Materials
Journal of Polymer Science, Part A: Polymer Chemistry | Year: 2016

Electroactive polyamides containing dense oligoaniline functionalizations (PAs) were synthesized via oxidative coupling polymerization followed by postpolymerization functionalization, and exhibit excellent solubility, good thermal stability and reversible electroactivity. Interesting spectroscopic changes that occurred through chemical oxidation have been shown, which demonstrate the potential of PAs as an electrochromic material. As a result, the electrochromic behaviors of PAs were investigated in detail, exhibiting high contrast value, moderate switching time, and satisfactory coloration efficiency. Tunable conductive and dielectric properties have also been accomplished by varying the incorporation of oligoaniline segments. © 2016 Wiley Periodicals, Inc. Source

Ouyang S.-L.,State Key Laboratory of Superhard Materials | Ouyang S.-L.,Jilin University | Li Z.-W.,Jilin University | Chen Y.-Z.,Jilin University | And 3 more authors.
Chemical Research in Chinese Universities | Year: 2011

Raman spectra and ultraviolet-visible(UV-Vis) absorption spectra of linear polyene molecule-canthaxanthin in n-hexane are measured and analyzed. In addition, the optimized structure of canthaxanthin was calculated via density functional theory(DFT) functional B3LYP. With decreasing the concentration, Raman scattering cross section (RSCS) of fundamental frequency is extremely high, and the UV-Vis absorption bands become narrower. The results of coherent weakly damped electron-Lattice vibration model were analyzed. Source

Qu G.-N.,State Key Laboratory of Superhard Materials | Qu G.-N.,Jilin University | Li D.-F.,Jilin University | Li Z.-L.,Jilin University | And 8 more authors.
Wuli Xuebao/Acta Physica Sinica | Year: 2010

We have measured the UV-visible absorption and Raman spectra of β-carotene which contains 9 CC conjugated double bond polyenes biological molecules in 9 kinds of solvents. The results showed that the Raman scattering cross-section for C-C and C=C stretching vibration bands of β-carotene increases linearly with the increase of solvent density. The mechanism is that β-carotene in high density solvent is less affected by perturbation, has higher structure order, more extended π electron delocalization, and stronger coherent weakly damping C-C bond vibration, which results in a large Raman scattering cross section. Studies on the influence of solvent density to molecular Raman cross section have not been reported. This paper is promising as on experimental hint on theoretical study of light scattering, and provides a reference for research of polyenes chain molecules and the development of optoelectronic devices. © 2010 Chin. Phys. Soc. Source

Yang J.-G.,State Key Laboratory of Superhard Materials | Yang J.-G.,PLA Air Force Aviation University | Sun C.-L.,Jilin University | Yang Y.-B.,PLA Air Force Aviation University | And 4 more authors.
Wuli Xuebao/Acta Physica Sinica | Year: 2012

Fermi resonance (FR) plays an important role in the spectral line identification and assignment in spectral analysis. It contains a wealth of physical laws which are urgently needed for research. In the present paper, we propose a new method of varying the refractive index of the solution to study the FR, which is based on the model of Onsager. The basic principle of this method is to use Raman scattering intensity (Raman scattering coefficient) changing with the refractive index of solution to study the FR. With this method we not only can give the relationship between the FR parameters and the refractive index of solution, but also find new spectrum phenomena (including the asymmetric shift of Fermi doublet and the FR tuned fundamental freguency of the overtone). In this article we provide a new research method to study the FR. © 2012 Chinese Physical Society. Source

Wang L.,State Key Laboratory of Superhard Materials | Ke F.,HIGH-TECH | Li Y.,State Key Laboratory of Superhard Materials | Wang Q.,Shandong Key Laboratory of Optical Communication Science and Technology | And 6 more authors.
Physica Status Solidi (B) Basic Research | Year: 2016

Theoretical and experimental methods have been conducted to study the high-pressure structures of CaWO4, which have never been definitely determined during the past decades. By using the CALYPSO method, in addition to the previously known tetragonal scheelite structure (I41/a), monoclinic fergusonite structure (I2/a), and the orthorhombic structure (Cmca) predicted by previous works, we have found two other new phases of CaWO4 at higher pressure: monoclinic P21/c and P21/m structures. Although the P21/c structure has the lowest energy (above 26.0GPa), synchrotron-radiation-based X-ray diffraction measurements show that only the P21/m structure stably exists above 38.0GPa. The kinetical hindrance of P21/c structure formation in the experiment has been attributed to its larger W-O coordination number than that of the P21/m structure at high pressure. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

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