Infrared observation of linear GeC3 trapped in solid Ar

Area of Science:

• Inorganic Chemistry
• Spectroscopy
• Computational Chemistry

Background:

• Understanding the structure of small clusters of group IV elements is crucial in materials science.
• Previous studies on silicon carbon clusters (SiC3) indicated cyclic isomers, while carbon clusters (C4) showed linear structures.

Purpose of the Study:

• To synthesize and characterize the linear germanium carbon cluster (GeC3).
• To determine the vibrational frequencies of linear GeC3 using spectroscopic methods.
• To compare the structural properties of GeC3 with related group IV clusters.

Main Methods:

• Synthesis of GeC3 clusters via dual laser ablation of carbon and germanium rods or a sintered germanium-carbon rod.
• Trapping of the synthesized clusters in solid argon at cryogenic temperatures (~10 K).
• Identification of vibrational modes using Fourier transform infrared (FTIR) spectroscopy.
• Verification of structural assignments using density functional theory (DFT) calculations (B3LYP/cc-pVDZ).

Main Results:

• The linear GeC3 cluster was successfully synthesized and its vibrational spectrum was observed for the first time.
• Two vibrational modes, nu(1)(sigma) and nu(2)(sigma), were identified at 1903.9 cm(-1) and 1279.6 cm(-1), respectively.
• Isotopic shift measurements using (13)C confirmed the assignments and were consistent with DFT predictions.

Conclusions:

• The study confirms the existence and linear structure of the GeC3 cluster.
• The observed vibrational spectra and computational results provide a detailed characterization of linear GeC3.
• This work contributes to the understanding of bonding and structure in group IV elemental clusters, contrasting with SiC3 and aligning with C4.