Structural Determination and Bonding Characteristics of the Gas-Phase Ta₂Si₂̅ Anion and Its Neutral: Anion Photoelectron Spectroscopy and Theoretical Studies

Abstract

The structures and bonding characteristics of Ta2Si2̅/0 clusters are investigated using anion photoelectron spectroscopy and quantum chemical calculations. The vertical detachment energy of the Ta2Si2̅ anion is measured to be 2.00 ± 0.08 eV using the 266 nm photon. It is found that the Ta2Si2̅ anion has three low-energy isomers with a C 2v symmetric Ta–Ta dibridged structural framework, all of which contribute to the experimental photoelectron spectrum, while the Ta2Si2 neutral also has a C 2v symmetric Ta–Ta dibridged structural framework. The charge-transfer from Ta atoms to Si atoms is discovered using atomic dipole moment corrected Hirshfeld analysis for the Ta2Si2̅ anion and Ta2Si2 neutral. Chemical bonding investigations show that both the Ta2Si2̅ anion and Ta2Si2 neutral have a strong covalent Ta–Ta bond, as well as σ and π double bonding patterns. Furthermore, the Ta atoms are linked together by a single 2c–2e Ta2 σ bond, whereas the Si atoms are linked together with the Ta atoms via four 2c–2e TaSi σ bonds, two 3c–2e TaSi2 σ bonds, one 4c–2e Ta2Si2 σ bond, and one 4c–2e Ta2Si2 π bond.

Anion Photoelectron Spectroscopy and Quantum Chemistry Calculations of Gas-Phase TaSi17̅ and TaSi18̅ Clusters: Structural Determination, Bonding Characteristics, and Multiplicity of Structural Forms

“…Our previous work utilized anion photoelectron spectroscopy and quantum chemistry calculations to explore Ta 1–3 Si 12 ̅ /0 , Ta 2 Si 2–21 ̅ /0 , , TaSi 2–15 ̅ /0 , and TaSi 16 ̅ /0 clusters . While the photoelectron spectrum of TaSi 17 ̅ has been documented, its precise structure and chemical bonding characteristics, alongside those of TaSi 18 ̅ /0 clusters, remained unexplored.…”