B_n(BO)_n~(2-),CB_(n-1)(BO)_n~-,and C_2B_(n-2)(BO)_n (n=5-12):Cage-like boron oxide clusters analogo

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A density functional theory (DFT) investigation has been performed in this work on the cage-like boron-rich boron oxide clus-ters Bn(BO)2n-,CBn-1(BO)-n,and C2Bn-2(BO)n (n = 5-12) which are boronyl analogues of the closo-boranes BnHn2-,monocarbo-ranes CBn-1H-n,and dicarboranes C2Bn-2Hn. These boron oxide clusters possess similar geometrical and electronic structures with the corresponding boranes and carboranes and prove to be three-dimensional (3D) aromatic compounds,consistent with the previously proposed BO/H isolobal analogy. Neutral C2Bn-2(BO)n species possess considerably high ionization potentials in the range 12.0-12.7 eV and CBn-1H-n monoanions have the vertical electron detachment energies in the range 6.6-9.4 eV at the DFT level. BO terminals singly bonded to the skeletal vertexes through a B atom possess the characteristic stretching vi-brational frequencies at about 2000 cm-1,clearly indicating the existence of B-O triple bonds in these clusters. Experimental syntheses and characterizations of these interesting clusters may expand the structural concepts of boron oxides and bring im-portant applications for boron oxide clusters as molecular devices in chemistry and new materials in boron neutron capture therapy. A density functional theory (DFT) investigation has been performed in this work on the cage-like boron-rich boron oxide clusters Bn (BO) 2n-, CBn- 1 (BO) -n, and C2Bn- 2 (BO) These are borononyl analogues of the closo-boranes BnHn2-, monocarbo-ranes CBn-1H-n, and dicarboranes C2Bn-2Hn. These boron oxide clusters are similar geometrical and electronic structures with the corresponding boranes and carboranes and prove to be three-dimensional (3D) aromatic compounds, consistent with the previously proposed BO / H isolobal analogy. Neutral C2Bn-2 (BO) n species possess considerably high ionization potentials in the range 12.0-12.7 eV and CBn-1H -n monoanions have the vertical electron detachment energies in the range 6.6-9.4 eV at the DFT level. BO terminals singly bonded to the skeletal vertexes through a B atom possess the characteristic stretching vi-brational frequencies at about 2000 cm-1 the existence of BO triple bonds in these clusters. Experimental syntheses and characterizations of these interesting clusters may expand the structural concepts of boron oxides and bring im-portant applications for boron oxide clusters as molecular devices in chemistry and new materials in boron neutron capture therapy.
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