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Published on: April 19, 2019
What Electronic Structures and Geometries of Carborane Mono- and ortho-, meta-, and para-Diradicals are Preferred?
Luis Serrano-Andrés1, Douglas J Klein1, Paul von Ragué Schleyer1
1Instituto de Ciencia Molecular, Universitat de València, Apartado 22085, ES-46071 Valencia, Spain, Texas A&M University at Galveston, Galveston, Texas 77553-1675, Center for Computational Chemistry, University of Georgia, Athens, Georgia 30602, Institut für Organische Chemie der Universität Erlangen-Nürnberg, Henkestrasse 42, D-91054 Erlangen, Germany, and Instituto de Química-Física Rocasolano, Consejo Superior de Investigaciones Científicas, Serrano, 119, ES-28006 Madrid, Spain.
Abstract:
Structures, relative stabilities, singlet-triplet gaps, and the ground-state character of mono- and diradicals derived from the three icosahedral carborane cage isomers have been computed by unrestricted broken-symmetry DFT and by CASPT2 methods. Whereas the bond dissociation energies (BDE) leading to the carborane monoradicals are close to the benzene BDE, the most stable carborane radicals are derived from dissociations of hydrogens farthest away from the carbon atoms. All the monomeric carborane diradicals are determined to have singlet ground states. However, the energetic accessibility of triplet states in some of the species offers the potential of building diradical multidimensional carborane network architectures with interesting magnetic properties.
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