【摘要】 用密度泛函理论对硅酸锆常温下的振动模进行模拟计算,并与实测的Raman和红外光谱进行了对比,解释了各振动模的归属。对硅酸锆晶体在升温过程中的Raman光谱的变化进行了研究。结果表明:随着温度上升,内振动模的红移明显,υ3(SiO4)伸缩振动模(B1g)红移最大,波数从常温时的1006cm–1红移至1823K时的937cm–1。各振动模不断展宽且相对强度减弱,表明硅酸锆在升温过程中逐渐无序化,但[SiO4]四面体并没有聚合。升温过程中硅酸锆分解成ZrO2和SiO2。更多还原

【Abstract】 The vibration modes of zircon were simulated by the density functional theory and compared with the experimental results of Raman and infrared spectroscopy.All the vibration modes were interpreted and assigned.Temperature dependence of Raman spec-tra of crystalline zircon was recorded in the temperature range from 298 K to 1 923 K.The results show that the significant shifts of internal Raman bands toward lower wave numbers with the increase of temperature,and the red-shift of the υ3(SiO4)Raman band(B1g)is the most obvious from 1 006 cm-1 to 937 cm-1.The increase in band half-widths and accompanying decrease of relative inten-sity suggests the zircon lattice becomes more disordered,but SiO4 tetrahedra remain stable and are still isolated with increase tem-perature.Zircon is decomposed to form zirconia and silica with increase of temperature.更多还原