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研究了四氢呋喃(THF)非共振拉曼光谱中反对称散射的贡献。在测量THF的非共振拉曼带的退偏比时发现,准转动式环折迭振动带及其组合带υ16和υ17虽是全对称振型,但其退偏比ρ约0.75,远大于其它普通全对称振动带的退偏比。从时间反演对称性和空间对称性分析证明,反对称极化率张量不为零,进一步估计其大小比对称部分小一个量级(或同量级)。反对称散射的重要贡献是υ16、υ17振动带大退偏比的重要原因。 相似文献
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本文首次观察了用MOCVD方法生长的GaxIn1-xP外延层的能带隙移动,并给出了GaxIn1-xP外延层光荧光(PL)峰能量随组分x的变化关系,结果表明PL是探测混晶组分的简单而有效的方法之一。 相似文献
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古壁画、陶彩颜料的拉曼光谱分析 总被引:19,自引:7,他引:12
本文利用拉曼光谱对河南班村遗址出土的仰韶彩陶陶彩以及河北磁县湾漳东魏北齐大型壁画墓中的壁画颜料进行了分析,成功的测定出陶彩及壁画颜料的成分。这一研究工作表明,拉曼光谱作为现代技术非常适合于易损和不允许取样的珍贵艺术品颜料的无损分析 相似文献
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利用简单的液相合成方法,在室温下制备了KMnF3圆盘状产物,盘的直径约为300nm.通过X射线粉末衍射(XRD)、透射电镜以及选区电子衍射对它的结构成分和物相进行了表征,发现圆盘形貌是由KMnF3小颗粒自组装而形成的.同时对样品的发光性质进行了研究,在416和438nm处观测到特别强的光发射,并对发射峰的来源进行了指认分析.与XRD数据计算得到的晶格参数相比,发现利用样品发光数据和公式Eem=-16963+164R,可以达到方便快捷地估算Mn-F之间距离和样品晶格常数的目的. 相似文献
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The GaxIn1-xP/GaAs heterostructures with different x values have been investigated by photoluminescence (PL), energy dispersive spectrum (EDS), and transmission electron microscopy (TEM). Experimental results suggested that the composition of epitaxial layers evidently affected the microstructure of the heterostructures. When x value was close to 0.5, the defects in the epitaxial layer decreased, and the lattice match between film and sub-strate approached optimum, Meanwhile, the heteroatructure provided a high luminescence efficiency. 相似文献
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A STUDY OF RAMAN SCATTERING AND INFRARED ABSORPTION SPECTRUM IN A NEW SERIES OF MERCURY-BASED HIGH-Tc SUPERCONDUCTOR (Hg,Mo)Sr2(Y1-xCax)Cu2O6+δ 下载免费PDF全文
Lattice vibrations of the (Hg,Mo)Sr2(Y1-xCax)Cu2O6+δ—a new series of mercury-based high-Tc superconductor are analyzed with the aid ofgroup theory. The vibrations of species are given. They are 4A1g+ B1g+ 5Eg+ 7A2u + B2u+ 8Eu. The 4A1g, B1g and 5Eg modes are Ramma active, the 6A2u and 7Eu are infrared active. Phonon vibration characteristics of the samples are studied using Raman scattering and infrared absorption spectra. The experimental results show that the typical phonon vibrational modes appear mainly at 145, 320, 440, 578, 592 and 645cm-1, The intensities of the 145, 320, 440, 578 and 645 peaks decrease with increasing Ca content x and the position of 645 peak moves to higher wavenumber slightly. In this article, the phonan modes are assigned and their variation behavior with increasing Ca content x are discussed. 相似文献