Enhanced Electrical Conductivity in a Substitutionally Doped Spiro-bis(phenalenyl)boron Radical Molecular Solid

We report the crystallization of a subsitutionally doped organic conductor based on a host lattice composed of spiro-bis­(phenalenyl)­boron radicals. Co-crystallization of solutions of spiro-bis­(9-oxido­phenalenone)­boron radical [PLY­(O,O)]2B mixed with selected amounts of spiro-bis­(9-oxido­phenalenone)­beryllium [PLY­(O,O)]2Be leads to the formation of a series of solid-state solutions of composition [PLY­(O,O)]2­B(1–x)Bex. The dopant molecules [PLY­(O,O)]2Be serve to introduce holes into the lattice of spins provided by the [PLY­(O,O)]2B radicals and lead to a systematic increase in the conductivity while decreasing the activation energy of the conduction process and leaving the solid-state structure relatively unperturbed. While the energies of the hole sites are expected to be high, the results are consistent with the interpretation of the electronic structure of [PLY­(O,O)]2B in terms of the resonating valence bond model.