Theoretical study of electronic spectra of linear carbon clusters HC_(2n)S(n =1-5)

摘要

In this work we report the structures and stabilities of linear carbon clusters HC_(2n)S(n =1-5) in theirground states using the B3LYP density functional. The rotational constants at the optimized geometriesgive excellent agreement with the experimental and previous theoretical values. The vertical excitationenergies of the 2~2n← X~2n transitions at the CASPT2level are3.16, 2.66, 2.05, 1.78,and1.55 eV,respec-tively, in good agreement with the corresponding observed values of 3.01, 2.48, 2.10, 1.84, and 1.65 eV.Also, the exponential-decay curves for these vertical excitation energies obtained from experiments andtheoretical calculations are illuminated.