Ag₆Cl₄: the first silver chloride with rare Ag₆ clusters from an ab initio study

Area of Science:

• Solid-state chemistry
• Computational materials science
• Inorganic chemistry

Background:

• Silver subhalides are underexplored materials with unique electronic and structural properties.
• Understanding bonding in silver compounds is crucial for developing new functional materials.
• Subvalent silver clusters are rare and exhibit unusual chemical bonding characteristics.

Purpose of the Study:

• To predict the existence and properties of a novel silver subhalide, Ag6Cl4.
• To investigate the unique electronic structure and bonding features of subvalent silver clusters within Ag6Cl4.
• To assess the stability and potential synthesizability of the predicted material.

Main Methods:

• Utilized Density Functional Theory (DFT) for first-principles calculations.
• Analyzed electronic structure, including 2e-6c bonds and d10-d10 interactions.
• Evaluated formation enthalpy and dynamical stability to predict synthesizability.

Main Results:

• Predicted the first diamagnetic semiconducting silver subhalide, Ag6Cl4.
• Identified rare subvalent Ag6 clusters with novel 2e-6c bonding and 1D argentophilic interactions.
• Confirmed 3D ionic connectivity facilitated by chloride anions and significant dynamical stability.

Conclusions:

• Ag6Cl4 exhibits unique bonding properties of Ag+ ions, previously observed only in metal-rich oxides.
• The predicted material represents a significant addition to the understanding of silver's special bonding.
• Ag6Cl4 is predicted to be synthesizable as a metastable phase, offering potential for experimental validation.