Study On The Electronic Structure Properties Of Hydrated Dodecaborate

Hydrated ions are ubiquitous in our daily lives and are the forefront of research in many disciplines such as atomic and molecular physics,physical chemistry and atmospheric environment.It is closely related to many important physical and chemical processes in nature,such as ion transport,protein stabilization,and aerosol formation.In particular,the microstructure and dynamic behavior of hydrated ions at the atomic level have been the focus of controversy in academia.As a typical representative of boranes,closo-dodecarborate(B₁₂H₁₂^2–)have a highly symmetric icosahedral geometry,whose delocalizedσelectronic system can stabilize two additional electrons,exhibiting unique elec tronic structural stability and thermodynamic stability.B₁₂H₁₂^2–and its derivatives have potential applications in many fields such as electrochemistry,nonlinear optics,and biopharmaceuticals,especially in the design of boron containing drug carriers for boron neutron capture therapy.Recent studies have shown that B₁₂H₁₂^2–is superchaotropic and can be used as broadband membrane carriers.However,B₁₂H₁₂^2–often works in the water environment,that involves complex interface problems,requiring appropriate cluster models to reveal microscopic mechanisms.In this dissertation,based on the gas phase hydrated cluster model,we reveal the lowest-energy structure,electronic structure stability,and thermodynamic stability of B₁₂H₁₂^2–·（H₂O）_n（n=1–12）through high-resolution anion photoelectron spectroscopy and high-level quantum chemical theoretical calculations.The results show that the hydration of B₁₂H₁₂^2–is driven by enthalpy at low temperatures,and the weak interaction between B₁₂H₁₂^2–and water molecules is mainly dominated by electrostatic interaction,supplemented by dispersion.Interestingly,during the microhydration of B₁₂H₁₂^2–,water molecules are most likely to aggregate to form a cyclic pentamer,followed by a book type hexamer.It is worth noting that there is a"plain"at n=9–11for the vertical detachment energy observed in the anion photoelectron spectroscopy experiment.Theoretical calculations have shown that there is a bicyclic pentamer structure of S₁₀ symmetry at n=10,which has very stable thermodynamic and electronic structural properties among low-energy isomers.It is believed that the research work in this dissertation can provide useful references for understanding the superchaotropic effect and microhydration dynamics at the atomic and molecular levels.