Structure and Bonding of Sc₃C₂ and La₃C₂ Clusters from MATI Spectroscopy and Theoretical Calculations

Area of Science:

• Physical Chemistry
• Materials Science
• Spectroscopy

Background:

• Transition metal-carbide clusters are crucial for developing novel materials and devices.
• Understanding their fundamental properties is key to advancing this field.

Purpose of the Study:

• To synthesize and characterize scandium and lanthanum trimer dicarbides (Sc3C2 and La3C2).
• To determine their structural, electronic, and vibrational properties.
• To investigate the effects of encapsulation within a fullerene.

Main Methods:

• Laser ablation metal cluster beam generation.
• Mass analyzed threshold ionization (MATI) spectroscopy.
• Theoretical calculations for structural and electronic analysis.

Main Results:

• Precise ionization energies and vibrational frequencies were obtained for neutral and ionic clusters.
• Both Sc3C2 and La3C2 adopt trigonal bipyramid structures (C2v for neutral, D3h for ionic).
• Neutral clusters have doublet ground states with unpaired electrons on metal atoms; ions are singlets.
• Metal-carbon bonding is primarily polar covalent.
• Encapsulation within C80 fullerene significantly alters cluster properties.

Conclusions:

• The study provides detailed insights into the properties of Sc3C2 and La3C2.
• Structural and electronic properties were elucidated through combined experimental and theoretical approaches.
• Encapsulation effects offer potential for tuning cluster characteristics in fullerene matrices.