Dissociation of hydrogen fluoride in HF(H(2)O)(7).

Area of Science:

• Physical Chemistry
• Computational Chemistry
• Quantum Chemistry

Background:

• Hydrogen bond (H-bond) arrangement significantly impacts water cluster energetics, structure, and chemistry.
• Previous studies established the importance of H-bond networks in molecular systems.

Purpose of the Study:

• To investigate the effect of H-bond orientation on hydrogen fluoride (HF) dissociation within a cluster of seven water molecules.
• To determine the energetic stability of different structural configurations of HF(H2O)7.

Main Methods:

• Utilized graph theory for structural analysis.
• Employed high-level ab initio methods for electronic calculations.
• Examined all possible H-bond orientations in cubic HF(H2O)7 clusters.

Main Results:

• Cubic structures of HF(H2O)7 were found to be more stable than other reported topologies.
• Electronic calculations revealed that ionized structures of cubie-HF(H2O)7 are energetically more favorable than non-ionized ones.
• The study identified specific H-bond arrangements that stabilize the ionized form.

Conclusions:

• Seven water molecules can potentially ionize hydrogen fluoride.
• H-bond orientation plays a critical role in the dissociation and ionization of HF in aqueous clusters.
• The findings provide insights into the fundamental interactions governing acid-base chemistry in small water clusters.