On the complex hydrogen-bond network structural dynamics of liquid methanol: Chains, rings, bifurcations, and lifetimes.

This article focuses on the detailed investigation of the hydrogen-bond (H-bond) network topology, structural dynamics, and electronic properties of bulk liquid methanol under ambient conditions using large-scale ab initio molecular dynamics (AIMD) simulations. The study reveals that nearly all methanol molecules participate in H-bonding, predominantly forming one-dimensional filamentary aggregates with significant branching (bifurcations) and cyclic motifs, especially tetrameric to hexameric rings, contrasting with the three-dimensional tetrahedral H-bond network of water. The analysis shows that five-membered rings are the most long-lived cyclic structures, and the effective molecular dipole moments of methanol molecules are strongly influenced by their local H-bond network topology due to polarization and charge transfer effects. Additionally, the computed self-diffusion coefficient and radial distribution functions agree well with experimental data, validating the simulation approach, while H-bond lifetimes indicate dynamic stability of medium-sized aggregates, highlighting the complex and cooperative nature of methanol's solvation environment.