Authors : D. K. Jha

Volume/Issue : Volume 11 - 2026, Issue 4 - April

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Google Scholar : https://tinyurl.com/3d5bbjkr

Scribd : https://tinyurl.com/yatw2fdk

DOI : https://doi.org/10.38124/ijisrt/26apr096

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Abstract : We report the theoretical characterization of a unique amido-bridged beryllium cluster, Be4(N-Ar)2. Density functional theory (DFT) calculations at the TPSS/def2-TZVP level reveal a stable, planar six-membered Be2-N-Be2-N ring core. The structure features distinct covalent Be-Be single bonds (2.049 Å) within the dumbbells. Multi-method analyses including Natural Bond Orbital (NBO), Localized Orbital Locator (LOL), and Electron Localization Function (ELF) demonstrate that the core is stabilized by significant Nitrogen lone-pair donation into the electron-deficient Beryllium centers (nN Be). Magnetic criteria (NICS(0) = -5.22 ppm) confirm the aromatic character of the framework. Furthermore, topological signatures from LOL and Laplacian mapping identify the Be-N bridges as possessing substantial charge-shift character.

Keywords : NBO, LOL, Charge Shift Bond, ELF, Laplacian, Cotton Effect.

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