Unraveling the Isoprene-Argon Complex: Insights from Pulsed Nozzle Fourier Transform Microwave Spectroscopy and Computational Analysis

Abstract

The study of various weakly bound complexes in the interstellar medium has posed significant challenges. Isoprene which is a fundamental organic molecule, and Argon which is a noble gas, form a complex that serves as an essential model system for examining molecular interactions in space. This research investigates the isoprene-Argon complex through the combination of Pulsed Nozzle Fourier Transform Microwave (PNFTMW) spectrometry and advanced computational methods. Utilizing a PNFTIR spectrometer, the study focuses on rotational transitions of both the Isoprene monomer and Isoprene-Argon complex, providing valuable insights into their vibrational and rotational characteristics. The discussion encompasses rotational constants (A, B, C) and dipole moment components (|μa|/D, |μb|/D, |μc|/D), shedding light on the complex's rotational behaviour and charge distribution along principal axes. The observed variations in rotational constants across diverse quantum chemical methods highlight the importance of method selection, while differences in dipole moments show the complex's sensitivity to computational nuances. The findings contribute to a better understanding of the Isoprene-Argon complex's molecular structure and its potential implications in interstellar chemistry. This multidisciplinary approach lays the groundwork for future investigations into molecular interactions and the refinement of computational models for improved predictive accuracy in describing complex molecular properties.