A theoretical analysis of the structure and properties of B26H30 isomers. Consequences to the laser and semiconductor doping capabilities of large borane clusters

Abstract

Decaborane(14), nido-B₁₀H₁₄, is the major commercially available molecular building block in boron cluster chemistry. The condensation of two such {nido-B₁₀} blocks gives the known isomers of B₁₈H₂₂ – a molecule used in the fabrication of p-type semiconductors and capable of blue laser emission. Here, we computationally determine the structures and thermodynamic stabilities of 20 possible B₂₆H₃₀ regioisomers constructed from the fusion of three {nido-B₁₀} blocks with the three subclusters conjoined by two-boron atom shared edges. In addition, density functional theory, time-dependent (TD)-DFT and multiconfigurational CASPT2 methods have been used to model and investigate the physical and photophysical properties of the three most stable of these isomers. Our findings predict these isomers to be potentially useful materials for the semiconductor industry, as high boron-content doping agents, and in the fabrication of new optical materials.