Pseudocarbynes: Charge-Stabilized Carbon Chains.

Area of Science:

• Materials Science
• Computational Chemistry
• Solid-State Physics

Background:

• Carbyne, a linear allotrope of carbon, remains elusive despite numerous claims of its synthesis.
• Recent transmission electron microscopy (TEM) images purportedly showing carbyne have instead revealed gold clusters.

Purpose of the Study:

• To investigate the influence of gold clusters on linear carbon chains.
• To determine if gold clusters contribute to the formation of pseudocarbyne structures.
• To explore the potential for designing novel metal-intercalated carbon compounds.

Main Methods:

• Ab initio calculations were performed on uncapped and capped linear carbon chains.
• Complexes of carbon chains with gold clusters were computationally modeled.
• Calculations included electron density analysis and Raman spectra simulations.
• Crystal structures of isolated and gold-intercalated carbon chains were analyzed.

Main Results:

• Gold clusters significantly alter the electron densities of carbon-carbon triple bonds (C≡C).
• This interaction leads to charge-stabilized pseudocarbyne structures, not true carbyne.
• Calculated Raman spectra for gold-intercalated pseudocarbyne structures align better with experimental data than isolated chains.
• Crystal structure analysis supports the formation of metal-intercalated compounds.

Conclusions:

• The presence of gold clusters leads to pseudocarbyne formation, explaining previous experimental observations.
• This study validates the existence of metal-intercalated carbon compounds.
• The findings pave the way for developing new materials based on metal-carbon interactions.