Co-crystallization of nonlinear optical diisopropylammonium pentaborate monohydrate: Structural, mechanical, thermal attributes, DFT precision modeling and docking studies

Abstract

In this study, we report the successful synthesis of diisopropylammonium pentaborate monohydrate single co-crystal. Using a controlled, slow evaporation technique, we promoted supramolecular growth, allowing for an in-depth examination of its structure. Single-crystal X-ray diffraction (XRD) analysis revealed its crystallographic details, which confirmed its triclinic crystal system, accompanied by predictive morphological analysis. Spectroscopic investigations, particularly UV–visible spectroscopy, unveil the crystal's remarkable transmittance in optical regime, showcasing a discernible direct energy gap of 5.49 eV. Photoluminescence behavior highlights an intense violet-coloured emission band at 400 nm after excited by a 250 nm radiation. The paper also comprehensively explores the crystal's mechanical and thermal attributes, in addition to conducting an intricate analysis of functional groups thereby confirming a triangular or tetrahedral coordination of boron atoms. Z-scan instrumentation aided in deducing non-linear absorption and refraction coefficients, substantiating the crystal's capability for third order NLO generation. Intermolecular H-interactions inherent within the crystal lattice are precisely probed via generating d_norm surfaces and their respective fingerprinting sketches. DFT modeling corroborates experimental observations, providing valuable knowledge of optimized geometric configurations, HOMO-LUMO orbitals, NPA, NBO distributions, analyses of hyperpolarizability, MEP intrinsic to DIPAPB. In the presence of DIPAPB, the replication of flaviviral proteins, such as those from the West Nile Virus (WNV), is effectively inhibited. This inhibition is attributed to the formation of a stable complex between DIPAPB and the WNV protein, thereby disrupting essential viral protein functions required for replication.