title: Concept and properties of an infrared hybrid single-beam spectrum and its application to eliminate solvent bands and other background interferences.
abstract: For infrared (IR) spectral measurements, if a quality single-beam background spectrum with desired intensity could be obtained, the contributions from solvent and other background components could be completely suppressed and their bands would not appear in a final transmittance/absorbance spectrum. In order to achieve this ideal but difficult goal, the concept of hybrid single-beam spectrum is introduced in this paper. The hybrid single-beam spectrum (φ h) is defined as a mixture of two single-beam spectra (φ b1 and φ b2) of the same sample but with different pathlengths (b1 and b2), namely, φ h = αφ b1+(1-α)φ b2, where α (0 ≤ α ≤ 1) is the component factor. The properties of the hybrid spectrum have been investigated. Under conditions of b2 > b1 ≥ 0.7 b2 and A max ≤ 0.60 (Amax is the maximum absorbance of b2 sample in the spectral range of interest), all the synthesized hybrid spectra are free from significant distortion regardless of the component factor. Therefore, the hybrid single-beam spectrum with desired intensity can be easily obtained simply by choosing an appropriate component factor. The proposed methodology has been demonstrated experimentally by the complete removal of the interference from the atmospheric water vapor and solvent.
authors.affiliation: School of Chemistry and Chemical Engineering, The Key Laboratory of Fuel Cell Technology of Guangdong Province, South China University of Technology, Guangzhou 510640, China.
authors.forename: Yujing
authors.initials: Y
authors.lastname: Chen
authors.affiliation: School of Chemistry and Chemical Engineering, The Key Laboratory of Fuel Cell Technology of Guangdong Province, South China University of Technology, Guangzhou 510640, China. Electronic address: wanghsh@scut.edu.cn.
authors.forename: Hai-Shui
authors.initials: HS
authors.lastname: Wang
authors.affiliation: Department of Chemistry, School of Science and Engineering, Kinki University, Osaka 577-8502, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Morisawa
authors.affiliation: Department of Chemistry, School of Science and Technology, Kwansei Gakuin University, 2-1 Gukuen, Sanda, Hyogo 669-1337, Japan.
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Ozaki
mesh_terms: D012997:Solvents / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods*
chemical_list: D012997:Solvents
keywords: Background elimination; Hybrid single-beam spectrum; Infrared spectroscopy; Solvent interference; Spectral distortion