Structure and stability of various states of the EuC and EuC2 molecules

B3LYP level density functional theory （DFT） and multiconfiguration self-consistent-field （MCSCF） level ab initio method calculations have been performed on the basis of relativistic effective core potentials to investigate the nature of EuC and EuC2 molecules. The computed results indicate that the ground states of EuC and EuC2 are ^12∑^＋ and SA2, respectively. Dissociation potential energy curves of the low-lying electronic states of EuC have been calculated using the MCSCF method, and the same level calculation on EuC2 indicates that the dissociation energy of EuC2 of ground state compares well with the available experimental data. The bond characteristic is also discussed using Mulliken populations.

Structure and stability of various states of the EuC and EuC2 molecules

B3LYP level density functional theory (DFT) and multiconfigurationself-consistent-field (MCSCF) level textit{ab initio} methodcalculations have been performed on the basis of relativisticeffective core potentials to investigate the nature of EuC andEuC₂ molecules. The computed results indicate that the groundstates of EuC and EuC₂ are ¹²sum⁺ and ⁸A₂respectively. Dissociation potential energy curves of the low-lyingelectronic states of EuC have been calculated using the MCSCF method,and the same level calculation on EuC₂ indicates that thedissociation energy of EuC₂ of ground state compares well withthe available experimental data. The bond characteristic is alsodiscussed using Mulliken populations.