First-principle study of geometries, electronic structures and vibrational spectra of neutral and anionic onion-like As@Ni₁₂@As₂₀

We present results of first-principle study for both neutral and anionic onion-like As@Ni₁₂@As₂₀. The ground-states of singly-charged and doubly-charged anions deviate from ideal I_h symmetrical geometry because of Jahn--Teller effect, whereas the triply-charged singlet and neutral quartet have similar stable geometries of I_h symmetry. The infrared and Raman spectra may provide a way to determine various charge states of this molecule with the same symmetry. Based on our systematical calculations, we suggest additional experimental measurements in order to determine the appropriate functional with great confidence, which should be important in the research for future quantum dot devices.