The effect of apodisation and finite resolution on Fourier transform infrared and Raman spectra

被引:14
作者
Parker, SF [1 ]
Tooke, PB
机构
[1] Rutherford Appleton Lab, ISIS Facil, Didcot OX11 0QX, Oxon, England
[2] British Petr Res Ctr, Sunbury TW16 7LN, Middx, England
关键词
FT-Raman; infrared; apodisation; resolution;
D O I
10.1016/S1386-1425(97)00163-7
中图分类号
O433 [光谱学];
学科分类号
0703 ; 070302 ;
摘要
The interferograms measured on Fourier transform infrared (FTIR) and Raman (FT-Raman) spectrometers are routinely apodised before the Fourier transform is carried out. The effects of finite resolution and different apodisation functions on synthetic bands of known Lorentz-Gauss character have been investigated. (The apodisation functions chosen were those commonly available on commercial FTIR and FT-Raman spectrometers). The effects are dramatic, the ratio of resolution/(true bandwidth) required to obtain less than 10% distortion (as judged by the peak height and width) in the band varied from 1 for boxcar to less than 0.2 for Norton-Beer (strong). Increasing Gaussian character of the band results in initially (i.e. at high resolution) the band being less altered by resolution and apodisation than a pure Lorentzian band. As the resolution is degraded, the band is more strongly affected. These results are explained in terms of the effect of truncation and distortion of the Fourier transform of the bandshape. A comparison of calculated and experimental results gave good agreement for the 1216 cm(-1) band of chloroform in deuterochloroform. The experimental results also showed an increasing degree of Gaussian character as the resolution became comparable with the full width at half height of the band. (C) 1997 Elsevier Science B.V.
引用
收藏
页码:2245 / 2252
页数:8
相关论文
共 6 条
[1]   ERRORS IN ABSORBANCE MEASUREMENTS IN INFRARED FOURIER-TRANSFORM SPECTROMETRY BECAUSE OF LIMITED INSTRUMENT RESOLUTION [J].
ANDERSON, RJ ;
GRIFFITHS, PR .
ANALYTICAL CHEMISTRY, 1975, 47 (14) :2339-2347
[2]  
GRIFFITHS P, 1986, FOURIER TRANSFORM IN
[3]   A REVIEW OF THE THEORY OF FOURIER-TRANSFORM RAMAN-SPECTROSCOPY [J].
PARKER, SF .
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY, 1994, 50 (11) :1841-1856
[4]   THE EFFECT OF APODIZATION AND FINITE RESOLUTION ON FOURIER-TRANSFORM RAMAN-SPECTRA [J].
PARKER, SF ;
PATEL, V ;
TOOKE, PB ;
WILLIAMS, KPJ .
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY, 1991, 47 (9-10) :1171-1178
[5]   THE SHAPES AND INTENSITIES OF INFRARED ABSORPTION BANDS - A REVIEW [J].
SESHADRI, KS ;
JONES, RN .
SPECTROCHIMICA ACTA, 1963, 19 (06) :1013-1085
[6]  
TOOKE PB, 1992, 8 INT C FOUR TRANSF, V1575, P248