Structure and Electronic Properties of Metalloboranes with General Formula Cp*3(μ‐H)M3B8H8 (M=Cr, Mo and W): The Effect of the Size of the Metal

Abstract

AbstractA family of Metalloborane of general formula Cp*3(μ‐H)M3B8H8 changing the metals M by Cr, Mo, and W, were theoretically studied via Density Functional Theory (DFT) incorporating the relativistic scalar (Scal) and spin‐orbit (SO) corrections. All the calculations agree with the experimental reports of the compound Cp*3(μ‐H)W3B8H8 and allowed us to describe the molecular and electronic structures of this family of Metalloborane. The electronic properties were modeled using reactivity indexes, Nucleus Independent Chemical Shift (NICS) indexes, Natural Bond Orbital (NBO), and other methods showing that the metallic core is aromatic. The spectroscopic properties were also studied via Time‐Dependent Density Functional Theory (TD‐DFT) showing a variation in the UV‐Vis spectra as the metallic atoms were changed. The most intense transitions are centered mainly over the metalloboranes cage with a decrease of the wavelengths as the metallic core gets bigger due to the increase of the HOMO‐LUMO gap. The Cp*‐Metalloborane core and the H‐Metalloborane core interactions were studied via the Morokuma‐Ziegler decomposition scheme, showing that the electrostatic interaction plays the most important role in the stabilization energy of the Cp*‐Metalloborane core. All our results suggest that the compound a (Cp*3(μ‐H)Cr3B8H8) and b (Cp*3(μ‐H)Mo3B8H8) will display similar properties to compound c (Cp*3(μ‐H)W3B8H8) and all of them are expected to have interesting properties.