Computational profiling of optical and NLO properties of diisopropylammonium perchlorate

This study provides a thorough computational and spectroscopic investigation of diisopropylammonium perchlorate, emphasizing its structural optimization, electronic configuration, surface interactions, hyperpolarizability, and optical characteristics. Density Functional Theory calculations were utilized to determine the optimized molecular conformation, energy states, and hyperpolarizability, offering insights into its nonlinear optical behavior. The calculated HOMO-LUMO energy gap of diisopropylammonium perchlorate is 3.8487 eV, along with a notable first-order hyperpolarizability of $2.1683\times 10-30$ esu. The frontier molecular orbitals and density of states were examined to assess electronic transitions and stability. Additionally, vibrational spectroscopy was employed to correlate theoretical predictions with experimental spectral data. The vibrational modes of the diisopropylammonium cation are primarily attributed to N–H stretching vibrations (3200–3500 cm⁻¹), C–H stretching of the isopropyl groups (2850–2960 cm⁻¹), and bending vibrations of the NH₂⁺ moiety (around 1600 cm⁻¹), suggesting strong hydrogen bonding interactions with the anionic counterpart. The optical properties, including infrared vibrational study and ultraviolet–visible spectra, were analyzed to explore potential photonic applications. The results enhance the comprehension of the compound's structural and electronic attributes, underscoring its relevance in advanced material applications.