A Simple ab Initio Model for the Solvated Electron in Methanol.

Area of Science:

• Computational chemistry
• Physical chemistry
• Quantum chemistry

Background:

• Understanding the solvation structure of electrons is crucial for various chemical processes.
• Previous estimates of the electron solvation structure in methanol lacked precise experimental agreement.

Purpose of the Study:

• To investigate the solvation structure of a solvated electron in methanol using ab initio calculations.
• To determine the precise arrangement of methanol molecules around a solvated electron.
• To compare computational results with experimental data.

Main Methods:

• Ab initio calculations of small anion methanol clusters.
• Inclusion of a polarized dielectric continuum model.
• Utilized coupled-cluster (CCSD), Møller-Plesset perturbation theory (MP2), and B3LYP density functional theory methods.
• Employed the augmented correlation-consistent polarized valence double-zeta (aug-cc-pvdz) basis set.

Main Results:

• Identified a lowest-energy structure featuring a tetrahedral arrangement of four methanol molecules.
• Observed OH bonds oriented towards the center of the tetrahedron.
• Calculated an optimum distance of ~1.8 Å from the tetrahedron center to hydroxyl protons, refining previous estimates.
• Successfully reproduced experimental values for radius of gyration (Rg), vertical detachment energy, and resonance Raman frequencies.
• Qualitatively reproduced the electron paramagnetic resonance (EPR) g-factor shift using density functional theory (DFT).

Conclusions:

• The study provides a refined model for the solvation structure of electrons in methanol.
• Computational findings align well with diverse experimental observations.
• The results enhance our understanding of electron-molecule interactions in polar solvents.