[[Zn-(CH3CH2OH)n]2+ Clusters Probed with Fluorescence Spectroscopy and Computation].

Area of Science:

• Physical Chemistry
• Materials Science
• Computational Chemistry

Background:

• Ethanol molecules exhibit characteristic fluorescence peaks.
• Metal ions can disrupt molecular structures and form new clusters.
• Understanding metal-ion-solvent interactions is crucial in various chemical processes.

Purpose of the Study:

• To investigate the cluster structures of zinc ions in ethanol solutions.
• To determine the impact of Zn2+ on ethanol molecule arrangements.
• To identify the predominant cluster formations using spectroscopic and computational methods.

Main Methods:

• Fluorescence spectroscopy was employed to observe changes in ethanol's optical properties.
• Density Functional Theory (DFT) calculations, specifically the B3LYP method, were used for structural optimization.
• Thermodynamic parameters were analyzed to assess cluster stability.

Main Results:

• Zn2+ addition induced a new fluorescence peak (350-380 nm) and weakened the original ethanol peak (275-330 nm).
• The first solvation shell of Zn2+ in ethanol comprises up to six ethanol molecules.
• DFT calculations identified six likely molecular cluster structures in solution.
• Experimental and theoretical fluorescence spectroscopy confirmed the generation of new [Zn-(CH3CH2OH)n]2+ clusters, predominantly with n=1-3.

Conclusions:

• Zinc ions significantly influence the structure of ethanol solutions, leading to the formation of specific metal-organic clusters.
• [Zn-(CH3CH2OH)n]2+ clusters, particularly for n=1-3, are the primary species formed.
• The combination of spectroscopic and DFT methods provides a robust approach for characterizing such molecular clusters.