仿岩浆岩玻璃相介观团粒结构类声子限制效应的拉曼光谱研究

Study on Confinement Effect of Phonon Like Modes for Mesoscopic Aggregation Structure of Glasses Phases in the Imitating Magmatic Rocks by Raman Spectra

应用微晶声子色散理论、量子化学从头计算与拉曼光谱(LWRS、RS)分析技术相结合的方法,系统地探测了仿超基性岩(MU)、仿基性岩(MB)、仿中性岩(MI)和仿酸性岩(MA)等4个系列玻璃相的介观团粒结构参数及其类声子限制效应,建立了各自的类声子色散曲线,进而获得了随着体系介观团粒尺度的增加,其低频端声学声子(横模与纵模)振动波数红移、中频及高频端的光学声子(横模与纵模)振动波数紫移、光学声子(横模)之拉曼谱峰的半高宽减小和其介观团粒尺度的变化范围增大等结论。这些结论不但丰富了低维非晶硅酸盐玻璃相及其熔体的类声子色散理论,而且开拓了拉曼光谱研究岩浆岩介观结构的新领域,为探索岩浆的结晶、演化和成矿规律提供重要理论依据及信息。

In the present paper,the mesoscopic aggregation structure parameters and the phonon confinement effect like modes of these glass phases in the imitating ultrabasic rock （MU）, imitating basic rock （MB）, imitating intermediate rock （MI） imitating acidic rock （MA） were detected by means of phonon dispersion theory,quatume chemical calculation （ab initio） and LWRS,RS analysis technology.The phonon dispersion curves like modes of the MU,MB,MI and MA have were established.It was obtained that as fast as the mesoscopic aggregation size was increasing,the low frequency changes of the phonics phonon like modes transverse wave （TA） longitudinal wave （LA） were red shifted,the medium high frequency changes of the optics phonon like modes transverse wave （TO） longitudinal wave （LO） were blue shifted,the width at half maximum of Raman spectra peak （FWHM） was decreasing and the change bound of the aggregation size was increasing.These conclusions not only enriched the theory of phonon dispersion like modes in the low dimension silicates and its melts,but also exploited new field of Raman spectroscopic study of mesoscopic structure in magmatic rocks.It provides important information for deliberating crystallization,evolution and ore-forming rule of natural magma.