摘要
首次报告在Ａ３Ｍ２Ｇｅ３Ｏ１２∶Ｃｒ（Ａ＝Ｃｄ２＋，Ｃａ２＋；Ｍ＝Ａｌ３＋，Ｇａ３＋，Ｓｃ３＋）锗酸盐石榴石体系中，Ｃｒ３＋离子室温下的红—近红外（Ｒ—ＮＩＲ）宽发射带光谱性质。随位于八面体格位上的Ａｌ３＋→Ｇａ３＋→Ｓｃ３＋和十二面体格位上的Ｃｄ２＋→Ｃａ２＋组成顺序变化，室温下，Ｃｒ３＋离子的４Ｔ２→４Ａ２能级跃迁的Ｒ－ＮＩＲ宽发射带，发射峰及光谱的长波和短波边逐渐向低能长波边移动。这是由于晶场强度减弱，阳离子的离子半径增大的结果。在镉（钙）铝和镉（钙）镓锗酸盐体系中，少量Ｓｃ３＋取代八面体上的Ａｌ３＋和Ｇａ３＋时，可使Ｃｒ３＋的Ｒ－ＮＩＲ荧光发射强度增强。
The spectral properties of the Cr 3+ broad emission band in A 3M 2 Ge 3O 12 ∶Cr (A= Cd 2+ ,Ca 2+ ;M= Al 3+ ,Ga 3+ ,Sc 3+ ) germanate garnets at room temperature are reported for the first time.In the order of Al 3+ →Ga 3+ →Sc 3+ and Cd 2+ →Ca 2+ ions which occupy the octahedral and duodeahedral sites,respectively,R-NIR broad emission band of 4T 2→ 4A 2 level transition,emission peak,and the spectral long wavelength and short wavelength sides of Cr 3+ shift to long wavelengths having lower energy.The reason is that the crystal field strengths in the octahedral decrease,while the cation ionic radii in the A 3M 2 Ge 3O 12 system garnets increase gradually.The R NIR emission intensity of Cr 3+ is increased with some Sc 3+ ions substitution for Al 3+ or Ga 3+ ions in octahedral sites.
出处
《光谱学与光谱分析》
SCIE
EI
CAS
CSCD
北大核心
1999年第4期550-552,共3页
Spectroscopy and Spectral Analysis
基金
国家自然科学基金
关键词
铬离子
激光材料
发射光谱
锗酸盐
石榴石
Broad emission band, Spectroscopy, Cr 3+ ion, Germanate garnet, Luminescence
