Jakubek Ryan S
NASA Johnson Space Center, 538008Jacobs Technology Inc, Houston, TX, USA.
Appl Spectrosc. 2023 Jan;77(1):62-73. doi: 10.1177/00037028221126197. Epub 2022 Sep 15.
Detailed information on the physics and chemistry of a sample can be derived from Raman band parameters. However, the Raman band observed by the detector contains artifacts from the instrument, complicating analysis of these details. To obtain Raman data that can be directly correlated to sample properties and to compare Raman spectra across instrumentation, instrumental effects must be accounted for. This is commonly performed for homogeneously broadened bands by determining the contribution of the slit function to the spectrum. However, there is currently no method for understanding instrumental effects on inhomogeneously broadened bands or a method to account for these effects when examining data and comparing data across instruments, though these analyses are commonplace. This shortfall injects an unknown error into the analyses and comparisons of inhomogeneously broadened Raman bands. This work derives a method of modeling inhomogeneous Raman bands as a continuum of homogeneous Raman bands spanning the width of the stochastic fluctuation energy well that causes inhomogeneous broadening. This model is combined with previous work to examine the effects of the slit function, intrinsic Raman band, stochastic energy well, homogeneously broadened Raman band, and slit width band parameters on the inhomogeneously broadened Raman band parameters. This model, for the first time, provides a quantitative description of the experimental parameters that effect the inhomogeneous Raman bands.
样品物理化学性质的详细信息可从拉曼光谱带参数中得出。然而,探测器观测到的拉曼光谱带包含仪器产生的伪像,这使得对这些细节的分析变得复杂。为了获得能够直接与样品性质相关的拉曼数据,并在不同仪器之间比较拉曼光谱,必须考虑仪器效应。对于均匀展宽的谱带,通常通过确定狭缝函数对光谱的贡献来进行此项操作。然而,目前尚无方法来理解仪器对非均匀展宽谱带的影响,也没有在检查数据和跨仪器比较数据时考虑这些影响的方法,尽管这些分析很常见。这一不足给非均匀展宽拉曼光谱带的分析和比较带来了未知误差。这项工作推导了一种将非均匀拉曼光谱带建模为跨越导致非均匀展宽的随机涨落能量阱宽度的均匀拉曼光谱带连续体的方法。该模型与之前的工作相结合,以研究狭缝函数、固有拉曼光谱带、随机能量阱、均匀展宽拉曼光谱带以及狭缝宽度谱带参数对非均匀展宽拉曼光谱带参数的影响。该模型首次对影响非均匀拉曼光谱带的实验参数进行了定量描述。