云南红宝石的激发和发光光谱

Excitation and Luminescence Spectra of Yunnan Ruby

报道了云南红宝石的光致发光特征,发光中心主要为 Cr^(3+).结合人工红宝石的光谱,用晶体场理论分析,对云南红宝石的激发和发射光谱进行了归属.研究发现,天然红宝石由于有较多的杂质元素存在,使其晶场作用比合成红宝石的弱,晶场对称性也偏低.Cr^(3+)与其它杂质元素间有能量传递.杂质元素对红宝石的某种发光(250nm 激发下的发光)有猝灭作用.我们认为红宝石日光下的发光(415nm、580nm 激发下的发光)对红宝石的颜色有贡献.红宝石的主色由 Cr^(3+)产生,杂质元素对红宝石的颜色深浅起调制作用.

The photoluminescence(PL)properties of Yunnan ruby was reported in this paper.Themajor luminescence center is Cr^(3+).Compared with the spectra of synthesized ruby and throughcrystal field consideration,the excitation and emission spectra were assigned correctly.It isfound that,as compared with that of synthesized ruby,the crystal field strength of naturalruby was softened and the symmetry of the occupied site was lowered by the impurities.Sincethe energy can be transfered between Cr^(3+)and other impure ions,the luminescence excited by250nm light is quenched.It is considered by the authors that the photoluminescences of rubyunder visible light(excited by 415 and 580nm)have contribution to its color.It is revealedthat the major color of ruby is caused by Cr^(3+),however the shade of color is adjusted by otherimpure ions.