氯氣-臭氧凡得瓦團簇之紫外吸收截面積 Absorption Cross Section of Ozone Chlorine Complex in the UV Region

dc.contributor 洪偉修 zh_TW
dc.contributor 林志民 zh_TW
dc.contributor Wei-Hsiu Hung en_US
dc.contributor Jim Jr-Min Lin en_US
dc.contributor.author 潘世傑 zh_TW
dc.contributor.author Shih-Chieh Pan en_US
dc.date.accessioned 2019-09-04T10:17:32Z
dc.date.available 2012-8-3
dc.date.available 2019-09-04T10:17:32Z
dc.date.issued 2012
dc.description.abstract 凡得瓦團簇的紅外光譜已經有相當多的研究,但是凡得瓦團簇在紫外光譜的研究卻相當的少見。使用分子束的方法可以產生凡得瓦團簇,但是要產生特定大小的凡得瓦團簇不是一件容易的事。本實驗利用分子束,產生了氯氣-臭氧之凡得瓦團簇,並且在248 nm、308 nm以及352 nm波長下,測量其吸收截面積。我們偵測吸收截面積的方法,有別於一般的吸收光譜法,是利用分子束與雷射交互作用後,偵測光分解後剩餘的分子數。此方法可以在不知道團簇與單體的濃度下,得知團簇與單體的吸收截面積比例。我們藉由調整分子束的膨脹條件來調整分子束中團簇大小的分布。由於248 nm非常接近臭氧的最大吸收峰,而氯氣在此波長沒有吸收;另一方面,在352 nm,氯氣的吸收遠大於臭氧。於是我們在248 nm及352 nm波長下,觀察了凡得瓦團簇與單體的吸收截面積比值。隨著團簇濃度的增加,團簇吸收截面積比從低濃度開始維持一個定值,到團簇濃度更大時則逐漸地上升。由於凡得瓦團簇形成的機制是由最小的尺寸開始,接著更大的團簇才會形成,所以我們可以知道在團簇濃度低的範圍內,團簇的組成是含一個氯氣以及一個臭氧。最後在308 nm,此波長氯氣以及臭氧皆有吸收。在團簇是氯氣及臭氧以1:1的組成狀態下,團簇的吸收截面積約為氯氣單體吸收截面積的2.070.12倍,約為臭氧單體吸收截面積的3.50.39倍,將團簇的吸收截面積除以兩個單體相加的吸收截面積的比值為1.30.16。而在248 nm以及352 nm的O3Cl2團簇與單體吸收截面積比值分別是0.970.05以及0.770.04。實驗結果顯示,由一個氯氣以及一個臭氧組成的凡得瓦團簇中,凡得瓦力的影響確實會造成吸收光譜帶的變化。 zh_TW
dc.description.abstract There have been numerous studies on the infrared spectra of weakly bound van der Waals (vdW) complexes. However, studies of vdW complexes in the UV-Vis region are relatively rare. Although it is common to synthesize vdW complexes in a molecular beam, to synthesize a size-specific complex is not trivial. Our previous work of ozone dimer shows that the absorption cross sections of the complexes are related to the complex sizes. In this work, we generated a molecular beam which contained ozone-chlorine vdW complexes, and measured the absorption cross section ratios of the ozone-chlorine 1:1 vdW complex to its monomers at 248 nm, 308 nm and 352 nm. We employed a new method for determining absorption cross section. The unique feature of this method is that we do not need the knowledge of absolute concentration. At 248 nm, absorption of ozone is very strong where chlorine shows no absorption. At 352 nm, absorption of chlorine is much stronger than ozone. Our data show that the absorption cross sections of the complex at 248 nm and 352 nm remain constant at low complex concentrations, indicating that we successfully synthesized the complex which composes of only one ozone and one chlorine. At 308 nm, both ozone and chlorine have considerable absorption cross sections. The result shows that the absorption cross section ratios of the complex to chlorine and ozone monomers are 2.070.12 and 3.550.39, respectively. And it also implies that the cross section ratio of the complex over the sum of the monomer’s cross sections is 1.30.16. At 248 nm and 352 nm, cross section ratios of the complex to the monomer sum are 0.970.05 and 0.770.04, respectively. We may conclude that for the ozone-chlorine complex, the van der Waals interaction perturbs the absorption spectra of monomers. en_US
dc.description.sponsorship 化學系 zh_TW
dc.identifier GN0699420792
dc.identifier.uri http://etds.lib.ntnu.edu.tw/cgi-bin/gs32/gsweb.cgi?o=dstdcdr&s=id=%22GN0699420792%22.&%22.id.&
dc.identifier.uri http://rportal.lib.ntnu.edu.tw:80/handle/20.500.12235/100975
dc.language 中文
dc.subject 凡得瓦團簇 zh_TW
dc.subject 吸收截面積 zh_TW
dc.subject 分子束 zh_TW
dc.subject van der waals complex en_US
dc.subject absorption cross section en_US
dc.subject molecular beam en_US
dc.title 氯氣-臭氧凡得瓦團簇之紫外吸收截面積 zh_TW
dc.title Absorption Cross Section of Ozone Chlorine Complex in the UV Region en_US
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