Planar Tetracoordinate Fluorine in Binary Clusters

Area of Science:

• Inorganic Chemistry
• Computational Chemistry
• Materials Science

Background:

• Planar tetracoordinate fluorine (ptF) species are exceptionally rare due to fluorine's high electronegativity.
• The existence and stabilization of such species in binary clusters remain largely unexplored.
• Understanding the electronic and structural properties of ptF is crucial for advancing chemical bonding theories.

Purpose of the Study:

• To computationally investigate the possibility of ptF species in binary alkali halide clusters.
• To determine the stable geometries and bonding characteristics of Li4F4- and Na4F4- clusters.
• To establish the first example of ptF centers within binary alkali halide cluster systems.

Main Methods:

• Density Functional Theory (DFT) calculations were employed to explore the potential energy surfaces of Li4F4- and Na4F4- clusters.
• Global and local minimum structures were identified and characterized.
• Analysis of bonding through charge distribution, electron localization function, and natural bond orbital methods was performed.

Main Results:

• The global minimum structures for both Li4F4- and Na4F4- clusters were found to possess a C2v symmetry.
• These stable structures feature a planar tetracoordinate fluorine (ptF) center.
• The stability of the ptF species is attributed to strong electrostatic interactions and multicenter ionic bonds.

Conclusions:

• The study successfully predicts the existence of ptF species in binary Li4F4- and Na4F4- clusters.
• These findings represent the first instance of ptF centers in binary alkali halide clusters.
• The results offer new insights into the bonding nature and stability of exotic fluorine species.