我国某金伯利岩管中混型金刚石的紫外形貌和光谱特征  

Ultra-Violet Photographs and Spectral Characteristics of Mixed Type Diamonds in a Kimberlite Tube in China

作　　者：范良明[1] 杨永富[1] 闻辂[1] Fan Liangming;Yang Yongfu;Wen Lu

机构地区：[1]成都地质学院

出　　处：《岩矿测试》1984年第4期339-343,I0006,I0007,共7页Rock and Mineral Analysis

摘　　要：众所周知,金刚石按含氮量分成Ⅰ型和Ⅱ型。Ⅰ型含氮高,氮浓度大于0.01%;Ⅱ型一般不含氮,氮浓度小于0.001%。Ⅰ型中,含顺磁氮的称为Ⅰb型,其余为Ⅰa型。根据红外吸收光谱中7—10微米范围内各吸收峰的出现情况及强度差别,Ⅰa型又分为ⅠaA型和ⅠaB型。Mixed type diamonds occur in porphyritic Kimberlite tube in China.It a-mounts to 6%of the total diamonds yield.Mixed type crystal of diamond is composed mainly of type n molecules and a less amount(about third to fifth of the crystal)of type I molecules.The crystals are colorless,transparent and small octahedra(most size<1mm).On the ultra-violet transparent pho-tographs,within the crystal,shows small black area of opacities,and outside of this area shows white area transparent under emissive ultra-violet light(wa-velenth 2370A).On the ultra-violet spectrogram,absorption edge of the black area is between 2916A---2970A,but the white area transmits ultra-violet light beginning at 2230 A>Its representing forbidden band width is 5.51 ev.On the infrared spectrogram,the black area shows strong absorption at 1175,1282,1370 cm-1 and week absorption at 1100 cm-1 that they were lead by rich bi-nitrogen and poly-nitrogen;But the white area have no absorption peak leading by impurities of nitrogen.Therefore,in a mixed type diamond,local small black area marks type I,and vast white area indicates type II.

关 键 词：金刚石 红外吸收光谱 氮浓度 光谱特征 含氮量 吸收峰 Ⅰ型 

分 类 号：TQ1[化学工程]