Theoretical study on the structures and properties of hydrogen-doped cationic carbon clusters CnH2+ (n=3-10)

Systematic study on the electronic/geometrical structures and the parity alternation effect of hydrogen-doped cationic carbon clusters CnH2+ (n = 3-10) have been carried out at the density functional theory level. The linear isomers of the clusters have been defined as the ground-state (G-S) isomers. The carbon chain with even-n is quasi-polyacetylene-like in configuration; whereas when n is odd, the carbon chain displays a quasi-polyacetylene-like structure that fades into a cumulenic-like arrangement towards the center of the chain. The even-n cations are more stable than the odd-n ones. Theoretical explanations for the trend of even/odd alternation have provided based on a series of properties of the systems. The findings accord with the relative abundance of CnH2+ species as recorded in mass spectrometric investigations. (C) 2014 Elsevier B.V. All rights reserved.