Study of possible photodissociation channels in linear carbon clusters [formula omitted

Abstract

Ab initio calculations are used to determine molecular properties of linear carbon clusters C n (n=3–6) in ground and electronically excited states relative to photodissociation processes. MRD-CI calculations predict that in C 3 and C 5 the singlet–triplet splitting between the 1Π u and 3Π u arising from the same configuration is about 1 eV similar as in C 2. The energy differences between 1Δ g and 1Σ g + corresponding to the same π g 2 or π u 2 configuration in C 4 and C 6 are less than 0.2 eV. Calculations support experimental finding that the energetically most favorable fragmentation channel for linear carbon clusters C n (n=4–6) corresponds to the loss of C 3 to give its partner fragment C n−3 . Further fragmentation channels are discussed.