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Updated: Jul 19, 2026
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Computational study of multiple-decker sandwich and rice-ball structures of neutral titanium-benzene clusters
1Department of Chemistry, University of San Diego, 5998 Alcala Park, San Diego, California 92110, USA. jkua@sandiego.edu
Abstract:
Density functional theory calculations were applied to systematically and directly compare the relative energetic stability of multiple-decker sandwich and rice-ball structures for a variety of neutral Ti(m)Bz(n) clusters (m = 1-4, n = 1-5). Almost all structures favored the multiple-decker sandwich structure, as observed experimentally for early transition metals. The strength of each metal-benzene interaction averages 37 kcal/mol and remains relatively constant for sandwiches with three or more Ti atoms. The most stable smaller rice-ball structures did not have eta(6)-Bz bound to a single metal atom. Instead, the preferred coordination was having the plane of the benzene molecule parallel to a Ti(2) bond or a Ti(3) face, leading to some distortion of the benzene ring. The larger rice-ball structures, on the other hand, preferred to weaken the metal-metal bonds and retain eta(6)-Bz bound to a single metal atom, a structural motif shared with sandwiches.
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