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dicmi

铜虫 (小有名气)

[交流] 如何计算禁带宽度?

已经知道了UV-VIS全波长的扫描图谱

按照文献讲的,是用
引用回帖:
λg(nm)=1240/Eg(eV)

波长取吸收峰的起始点

这里吸收峰的起始点是什么意思呢?

作吸收起始点的切线,然后交于x轴为λ

吸收起始点是怎么确定的?

搜了好多资料,都没有详细的描述

紧急求助~~

谢谢各位大人~~

[ Last edited by nxl5096224 on 2009-1-27 at 18:55 ]
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hot_cool

金虫 (小有名气)

This is one way ?!

★ ★
daiqiguang(金币+2):谢谢应助
To my knowledge, this is one way to determine the absorption edge: find the inflection point on the absorption band in the higher wavelength/lower energy region; draw a tangent line at this point and extend all the way to the x axis; the intercept on the x axis is determined as the absorption edge.

In some case, if higher wavelength side is close to a linear fit, some people just find the intercept of this straight line at the x axis.

To a physicist, they would say that we need to figure out what type of charge transfer transition we have. If necessary, the plot should be also converted into Kubelka-Munk unit. A general power law can be then used to determine if the transition is direct or indirect; allowed or forbidden. Anyway, that is really confusing, at least to me.

[ Last edited by hot_cool on 2007-3-23 at 00:38 ]
14楼2007-03-23 00:36:24
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