SiO_2-Al_2O_3-Na_2O(K_2O)系列淬火熔体的高温高压合成及其LRM研究

High Temperature and High Pressure Syntheses of SiO 2-Al 2O 3-Na 2O(K 2O) Quenching Melts and Their Laser Raman Microprobe Study

本文采用合成溶胶凝胶中间体的技术方法，降低了硅酸盐熔体的熔化温度，并在１７５０～１８５０℃和２．０～４．０ＧＰａ条件下合成出９个ＳｉＯ２－Ａｌ２Ｏ３－Ｎａ２Ｏ（Ｋ２Ｏ）系列淬火硅酸盐熔体。淬火熔体中Ｎａ（Ｋ）／Ａｌ１，属过铝质硅酸盐熔体。其激光拉曼微探针（ＬＲＭ）研究表明：随压力增大，Ｔ－Ｏｎｂ在高频区（９００～１２００ｃｍ－１）的对称和反对称伸缩振动频率明显减小；过铝质熔体中存在六配位铝，且随压力增大，铝的配位数可能有从四配位向六配位转化的倾向。

It is shown in this paper that intermediate bodies synthetized by sol-gel technique can lower the melting points of melts. The authors synthetized 9 quenching silicate melts in SiO 2-Al 2O 3-Na 2O(K 2O) series at 1750～1850℃and 2.0～4.0GPa. The Laser Raman Microprobe (LRM) study of these quenching melts has obviously shown that within the high frequency region (900～1200cm -1 ), the higher the pressure, the smaller the frequency of T-Onb symmetry and antisymmetry stretching vibration. The silicate melts of Na(K)/Al<1 may have six_coordination aluminum, and the aluminum tends to transform its coordination number from four_coordination to six_coordination when the pressure of silicate melts become higher.