The electronic structure of linear Beryllium chains %(in particular, Be$_5$ and Be$_{10}$) has been theoretically studied by using {it ab initio} methods. It turns out that, for internuclear distances close to the equilibrium structure, two partially filled edge orbitals (``end states'') localize at the chain ends. This gives rise to two low-lying states, a singlet ground state, $^1Sigma_g$, and a quasi-degenerated triplet, $^3Sigma_u$. The energy splitting goes rapidly to zero as the number of atoms in the chain is increased. Preliminary investigations indicate that this could be a general behavior shared by the metals belonging to the Groups 2 and 12.
End states and singlet triplet degeneracy in linear atomic chains
MONARI, ANTONIO;BENDAZZOLI, GIAN LUIGI;
2008
Abstract
The electronic structure of linear Beryllium chains %(in particular, Be$_5$ and Be$_{10}$) has been theoretically studied by using {it ab initio} methods. It turns out that, for internuclear distances close to the equilibrium structure, two partially filled edge orbitals (``end states'') localize at the chain ends. This gives rise to two low-lying states, a singlet ground state, $^1Sigma_g$, and a quasi-degenerated triplet, $^3Sigma_u$. The energy splitting goes rapidly to zero as the number of atoms in the chain is increased. Preliminary investigations indicate that this could be a general behavior shared by the metals belonging to the Groups 2 and 12.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
