(Sr1-xBax)2SiO4固溶體可作為螢光粉主晶體結構材料，然而，目前尚未有此系列固溶體之詳細晶體結構變化資料。本研究利用固態反應法合成一系列(Sr1-xBax)2SiO4固溶體粉末樣品，並利用X光粉末繞射圖譜和Rietveld method進行晶體結構精算，其資料包含晶格常數、結構參數、陽離子(Sr2+、Ba2+)佔據格位分佈趨勢隨化學成份變化之關係，並嘗試觀察此系列固溶體之拉曼光譜隨化學成份變化影響。
由X光粉末繞射圖譜顯示本研究合成之一系列(Sr1-xBax)2SiO4固溶體粉末樣品皆以斜方晶系ortho相單一結構為主，但由X光粉末繞射圖譜的變化顯示，在Ba2+離子含量低於約25 mole％的固溶體樣品(X≦0.25)還觀察到數根不屬於斜方晶系ortho相結構的繞射峰，利用高溫X光粉末繞射實驗觀察額外繞射峰隨溫度變化的消長，驗證其為調整型結構(modulated structure)的衛星繞射峰，並由JANA2006軟體分析其繞射峰對應的米勒指數，此外，由衛星繞射峰值強度減弱的現象顯示當Ba2+離子含量約在25 mole％以下時為調整型結構IC相。
並從Rietveld method晶體結構精算結果觀察到此系列固溶體晶體結構中，Sr2+/Ba2+陽離子具有格位優選的特性。因不同格位在三維晶體結構中具有不同的排列方式，其陽離子格位優選影響配位環境中之特定鍵長變化較為顯著，進而造成特定方向之晶格常數變化具有非線性的行為。
本研究首次在(Sr1-xBax)2SiO4固溶體粉末樣品中，觀察到Sr2+/Ba2+陽離子具有格位優選的特性，以及調整型結構與固溶體陽離子比例變化的關係，期望這些結果應可對此系列之螢光粉的發光波長變化機制提供更進一步的了解。

The crystal structural variations in Strontium-Barium orthosilicate (Sr1-xBax)2SiO4 solid solution series as a function of the chemical composition were studied by using X-ray powder diffraction and analyzed using the Rietveld method, which enables us to obtain the information of crystal structure including cell parameters, cation distribution and structure parameters. The Rietveld method results indicate the cation distribution has the preference of Ba2+ ions occupied to the ten-coordinated site M(1) and Sr2+ ions occupied to the nine-coordinated site M(2) in the solid solutions. Due to the two lattice sites have different site environment, the lattice constants increase nonlinearly with increasing Ba-content should be attributed to the variations of the specific bond lengths in the specific direction of the lattice.
In this study, the satellite diffraction peaks of the incommensurate structure are observed from the X-ray powder diffraction data. The results indicate the crystal structure in the range below values of around 25 mol% Ba2SiO4 (X≦0.25) should be an incommensurate structure.

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中文部分：

胡瀚陽 (2013). "探討Sr2SiO4同分異構物形成與晶粒尺寸關係及其高溫行為." 國立成功大學地球科學研究所碩士論文.