Quantum chemical study of NbSi5−/0 clusters: structures and electron detachment energies

Tóm tắt

The structures and properties of the NbSi₅^−/0 cluster have been studied using density functional theory (DFT) and the CASPT2 method. The ground states of the negatively charged and neutral clusters were established as the ¹A₁ and ²B₁ states of a tetragonal bipyramidal isomer with C_4v symmetry. The adiabatic and vertical detachment energies (ADE and VDEs) of the transition from the anionic ground state to the neutral ground state were found to be 2.72 and 2.74 eV, respectively. A vibrational progression with three peaks at a frequency of 212 cm⁻¹ was observed for this transition in the Franck-Condon factor simulation. Furthermore, the VDEs of the transitions to the excited ²B₁, 1²A₁, 1²E, 2²E, and 2²A₁ states were computed as 3.10, 3.32, 3.77, and 4.67 eV, respectively. The recorded photoelectron spectrum of the NbSi₅⁻ cluster was elucidated by the transitions to the ²B₁, 1²A₁, 1²E, and 2²E states.