High-Throughput\nComputational Screening of Hydrocarbon\nMolecules for Long-Wavelength Infrared Imaging

The development of organic or sulfur/organic hybrid polymeric\nmaterials\nfor infrared (IR) thermal imaging applications has attracted significant\ninterest as an alternative to expensive semiconductor transmissive\nmaterials, particularly for long-wavelength IR (LWIR, 1250–800\ncm<sup>–1</sup>/8–12.5 μm). To accelerate the\ndesign of new candidate IR polymers with enhanced LWIR optical transparency,\nwe have developed a protocol that integrates density functional theory\ncalculations for simulating IR spectra (including both frequencies\nand absorption intensities of the vibrations) with high-throughput\nscreening. This approach enables us to explore novel hydrocarbon molecules\nwith improved LWIR transmittance which retain reactive groups conducive\nto polymerization with sulfur. The aim is to incorporate novel candidate\nmolecules with high predicted IR transparency into polymeric materials,\nnamely chalcogenide hybrid sulfur polymers synthesized by the inverse\nvulcanization of elemental sulfur. Starting from a relatively large\nlibrary of unsaturated 35,238 hydrocarbons, this study introduces\na set of promising candidates whose high LWIR percent window transparency\nvalues (<i>w</i>T) and chemical structures are expected\nto produce novel transparent hybrid sulfur/organic plastic materials.