Estimation of dielectric-response functions using micro- to macro-scaling of DFT-calculated IR spectra

Detection of infrared (IR) spectrum features of target molecules can be achieved by comparison experimentally measured spectra to template spectra within a database. This study continues presentation of the concept of using density functional theory (DFT) for calculation of template spectra. DFT-calculated spectra are well posed for comparison to measured spectra, to the extent of their scalability to larger space–time scales. Specifically, the focus of this study is the scalability of DFT-calculated IR spectra with respect to meso- and macroscales, characteristic of dielectric response as measured using different IR spectroscopies. A case-study analysis concerning IR-spectra scalability for a set of energetic materials is described. This analysis provides another example of calculating template spectra for potential detection of target molecules, which are of major interest using IR spectroscopies.