Humidity-Induced Spectral Shift in a Cross-Dispersion Echelle Spectrometer and Its Theoretical Investigation
LIU Ke-ling1, HUANG Mao2, Hieftje Gary M3
1. Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China 2. Library of Chinese Academy of Sciences, Beijing 100190, China 3. Department of Chemistry, Indiana University, Bloomington IN 47405, USA
Humidity-Induced Spectral Shift in a Cross-Dispersion Echelle Spectrometer and Its Theoretical Investigation
LIU Ke-ling1, HUANG Mao2, Hieftje Gary M3
1. Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China 2. Library of Chinese Academy of Sciences, Beijing 100190, China 3. Department of Chemistry, Indiana University, Bloomington IN 47405, USA
摘要： The relationship between ambient relative humidity H and the position shift of a spectral line was investigated both experimentally and theoretically. An echelle-based ICP emission spectrometer equipped with a CID detector was used for experimental verification of the derived model. The shift of a spectral line is quantitatively described by two defined spectral shift functions: Δλx(x, λ, H) (in the x direction of the CID detector) and Δλy(y, λ, H) (in the y direction of the CID detector). Experimental results indicate that Δλx(x, λ, H) does not change with a variation in ambient relative humidity, but Δλy(y, λ, H) does. A spectral shift equation, i.e. an empirical second-order polynomial equation, can be used to describe the relationship between Δλy(y, λ, H) and H. Based on the classical dipole model, classical mechanics and electrodynamics the empirical spectral-shift equation involving Δλy(y, λ, H) and H was theoretically deduced. The theoretical result is in good agreement with the experimental findings. The theoretical results indicate that the coefficients of the empirical spectral-shift equation are related to the basic physical parameters of materials and the geometric configuration of the echelle CID ICP-AES, and also provide physical meaning to the coefficients of the empirical shift equation obtained experimentally.
关键词：Emission spectrometry;Position shift of a spectral line;Spectral-shift equation
Abstract：The relationship between ambient relative humidity H and the position shift of a spectral line was investigated both experimentally and theoretically. An echelle-based ICP emission spectrometer equipped with a CID detector was used for experimental verification of the derived model. The shift of a spectral line is quantitatively described by two defined spectral shift functions: Δλx(x, λ, H) (in the x direction of the CID detector) and Δλy(y, λ, H) (in the y direction of the CID detector). Experimental results indicate that Δλx(x, λ, H) does not change with a variation in ambient relative humidity, but Δλy(y, λ, H) does. A spectral shift equation, i.e. an empirical second-order polynomial equation, can be used to describe the relationship between Δλy(y, λ, H) and H. Based on the classical dipole model, classical mechanics and electrodynamics the empirical spectral-shift equation involving Δλy(y, λ, H) and H was theoretically deduced. The theoretical result is in good agreement with the experimental findings. The theoretical results indicate that the coefficients of the empirical spectral-shift equation are related to the basic physical parameters of materials and the geometric configuration of the echelle CID ICP-AES, and also provide physical meaning to the coefficients of the empirical shift equation obtained experimentally.
Key words：Emission spectrometry;Position shift of a spectral line;Spectral-shift equation
通讯作者:
LIU Ke-ling
E-mail: klliu@home.ipe.ac.cn; kl_liu@sina.com
引用本文:
LIU Ke-ling1, HUANG Mao2, Hieftje Gary M3 . Humidity-Induced Spectral Shift in a Cross-Dispersion Echelle Spectrometer and Its Theoretical Investigation[J]. 光谱学与光谱分析, 2010, 30(09): 2555-2559.
LIU Ke-ling1, HUANG Mao2, Hieftje Gary M3 . Humidity-Induced Spectral Shift in a Cross-Dispersion Echelle Spectrometer and Its Theoretical Investigation. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2010, 30(09): 2555-2559.
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