Dissertation > Mathematical sciences and chemical > Physics > Solid State Physics > Solid nature of the > Optical Properties > Luminescence

The Crystal and Synthetics under Cathode Luminescence Characteristic’s Research

Author GuoPu
Tutor BaiFeng
School Chinese Geology University (Beijing)
Course Gemological
Keywords Cathodoluminescence Crystal and its synthetic products Luminescence centers
CLC O482.31
Type Master's thesis
Year 2011
Downloads 78
Quotes 0
Download Dissertation

This thesis is optional Crystal amethyst, topaz and rock crystal (211) cathodoluminescence BY-1 instrument as an object of study, the test sample luminous color, strength and internal structure characteristics. Comparative Analysis of the light-emitting characteristics of various colors crystal and its synthetic products, draw the cathodoluminescence law of the crystal. Test conditions: voltage 7-8kv, current 1500μA microscope magnification of 10 times. The colorless crystal cathodoluminescence weak to none, a few weak blue-violet. Weak - moderate red light emitting of the synthetic product, occasionally a blue light-emitting; cathode luminescence of the yellow crystals as a weak - moderate blue violet portion of the sample to a strong red-orange, synthetic yellow crystal as a weak - moderate orange-red light; the amethyst cathodoluminescence both blue-violet and red light, only the red light-emitting synthetic amethyst, amethyst luminous intensity higher than synthetics; topaz and amethyst are of color from shallow to deep, and its the cathodoluminescence intensity gradually increases, the in cathodoluminescence observe some of the characteristics of the crystal internal structure: fractured, the gas-liquid package body, ribbon, seed crystal plate. The combined Crystal Color Genesis theory and Cathodoluminescence explore Crystal the cathodoluminescence mechanism: colorless crystal of pure crystals of SiO2 and rarely contain structural defect and impurity ions, cathodoluminescence weak - no. Synthetic colorless crystal in the growth process to produce some structural defects luminescence center, or the impurities contained in the dopant ions will produce moderate - strong red light. Amethyst its color and composition of the synthetic products of FeO contained 4 4 - hole color center, the cathodoluminescence red, amethyst also contains trace aluminum and blue-purple. Citrine presented containing Al3 O-violet light, containing Fe3 impurity ions was orange-red shade, topaz can be presented simultaneously two colors, orange red synthetic topaz. Amethyst, topaz, synthetics cathodoluminescence characteristics differences: the crystal its Color Genesis synthetics difference; different features of both the internal structure; synthetic crystal growth process defects; crystal and The products of the synthesis by the length of the irradiation time and intensity will cause its cathode luminescence characteristics of the difference. There are three aspects: sample aspects, the sample size, shape, thickness and color of the experimental results influence factors affecting the cathode luminescence of experimental results; instrument debugging aspects, the electron gun voltage and current of the regulator; internal structural characteristics of the observed aspects have a certain degree of difficulty .

Related Dissertations
More Dissertations