The analysis of Figure , Figure , Figure , Table , and Table collectively highlights the effectiveness of Density Functional Theory (DFT) in accurately identifying the various isomers of TCBD using different hierarchical functionals. DFT proves capable of predicting molecular geometries and vibrational modes across the isomers, showcasing its utility in computational chemistry. However, distinguishing between the isomers solely based on their infrared (IR) spectra presents challenges, as many of the vibrational peaks overlap or are too similar to provide clear differentiation. This indicates the limitations of relying exclusively on IR spectroscopy for distinguishing structural variations among isomers. Consequently, alternative analytical techniques-such as nuclear magnetic resonance (NMR) spectroscopy, Raman spectroscopy, or advanced computational methods-are needed to enhance the resolution and provide a more comprehensive identification of TCBD isomers. Combining multiple approaches may lead to more accurate and reliable molecular characterization.