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Updated: Jul 9, 2026
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Linear C(n) clusters: are they acetylenic or cumulenic?
Shujiang Yang1, Miklos Kertesz
1Department of Chemistry, Georgetown University, Washington DC 20057-1227, USA.
Abstract:
Uncapped linear Cn clusters have been studied with hybrid density functional theory focusing on the geometry, HOMO-LUMO gap, and the longitudinal optical (LO) vibrational mode. The latter two correlate well with the bond length alternation (BLA) of the optimized geometry. Due to end effects, the BLA is not constant along the chains. The degree of BLA changes continuously with increasing n: starting with essentially nonalternating structures (cumulenic), then turning into strongly alternating (acetylenic) structures. This transition has not yet been described or characterized and occurs at relatively large values of n. The implications for the widely observed characteristic LO vibrational bands of linear carbon clusters are discussed.
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