摘要
Most existing studies assign a polyynic and cumulenic character of chemical bonding in carbon-based chains relying on values of the bond lengths.Building on our recent work,in this paper we add further evidence on the limitations of such an analysis and demonstrate the significant insight gained via natural bond analysis.Presently reported results include atomic charges,natural bond order and valence indices obtained from ab initio computations for representative members of the astrophysically relevant neutral and charged HC_(2k/2k+1)H chain family.They unravel a series of counter-intuitive aspects and/or help naive intuition in properly understanding microscopic processes,e.g.,electron removal from or electron attachment to a neutral chain.Demonstrating that the Wiberg indices adequately quantify the chemical bonding structure of the HC_(2k/2k+1)H chains—while the often heavily advertised Mayer indices do not—represents an important message conveyed by the present study.
基金
financial support from the German Research Foundation(DFG Grant No.BA 1799/3-2)in the initial stage of this work and computational support by the state of Baden-Württemberg through bw HPC and the German Research Foundation through Grant No.INST 40/575-1 FUGG(bw Uni Cluster 2.0,bw For Cluster/MLS&WISO 2.0/HELIX,and JUSTUS 2.0 cluster)