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Updated: Jan 13, 2026
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
The simplest planar tetracoordinate carbon: CLi3H
Chagan Dari1, Guang-Ren Na1, Li-Juan Cui1
1Institute of Atomic and Molecular Physics, Jilin University, Changchun 130023, China.
None:
Although numerous planar hypercoordinate atoms have been reported, we describe the first planar tetracoordinate carbon (ptC) stabilized by a distinct electronic mechanism. In the global minimum C2v structure of CLi3H+, the ptC is bonded to one hydrogen and three lithium atoms. This structure lies over 39 kcal/mol below the next isomer on the potential energy surface. Its stabilization arises solely from direct carbon ligand interactions, without contributions from ligand-ligand bonding. The carbon atom adopts a 2s22pσ12pπ22pπ'1 configuration, forming a strong C-H σ bond, while the C-Li interactions are weak and polar. CLi3H+ is therefore the smallest electron-deficient planar hypercoordinate species known, revealing a new bonding motif in cluster chemistry.
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