Evidence for the Superatom-Superatom Bonding from Bond Energies

Area of Science:

• * Computational chemistry and condensed matter physics.
• * Investigating novel bonding mechanisms in metal clusters.

Background:

• * Superatoms, metal clusters with specific valence electron counts, can form superatomic molecules via super valence bonds (SVBs).
• * Previous research verified SVBs through orbital shapes; this study explores bond energy as further evidence.

Purpose of the Study:

• * To investigate bond energy as a criterion for superatom-superatom bonding (SVBs).
• * To design and analyze Zn-Cu and Mg-Li superatomic molecules using density functional theory.

Main Methods:

• * Density Functional Theory (DFT) calculations.
• * Design of binary superatomic molecules (e.g., (Zn4)2, (Zn3Cu)2).
• * Chemical bonding analysis and electron localization function (ELF) analysis.

Main Results:

• * Calculated bond energies confirm SVBs in designed Zn-Cu and Mg-Li superatomic molecules.
• * Bond energies increase and bond lengths decrease with increasing bond order (nonbond to triple bond).
• * Electron localization function analysis shows similarity between SVBs and classical atomic bonds.

Conclusions:

• * Bond energies provide strong evidence for the existence of superatom-superatom bonding (SVBs).
• * The behavior of SVBs in terms of bond energy and length parallels classical chemical bonds.
• * This work offers new insights into superatomic cluster bonding.