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Self-assembled guanine ribbons as wide-bandgap semiconductors

A. Calzolari·R. Di Felice·E. Molinari·a. Garbesi
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Abstract

We present a first principle study about the stability and the electronic properties of a new biomolecular solid-state material, obtained by the self-assembling of guanine (G) molecules. We consider hydrogen-bonded planar ribbons in isolated and stacked configurations. These aggregates present electronic properties similar to inorganic wide-bandgap semiconductors. The formation of Bloch-type orbitals is observed along the stacking direction, while it is negligible in the ribbon plane. Global band-like conduction may be affected by a dipole-field which spontaneously arises along the ribbon axis. Our results indicate that G-ribbon assemblies are promising materials for biomolecular nanodevices, consistently with recent experimental results.

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A. Calzolari, R. Di Felice, E. Molinari, a. Garbesi. 2001-10-30. Self-assembled guanine ribbons as wide-bandgap semiconductors. https://doi.org/10.1016/s1386-9477(02)00343-0

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