Zero point motion effect on the electronic properties of diamond, trans-polyacetylene and polyethylene

It has been recently shown, using ab-initio methods, that bulk diamond is characterized by a giant band–gap renormalization (∼ 0.6 eV) induced by the electron–phonon interaction. This result casts doubt on the accuracy of purely electronic calculations. In this work we show that in polymers, compared to bulk materials, due to the larger amplitude of the atomic vibrations the real excitations of the system are composed by entangled electron–phonon states. We prove as the charge carriers are fragmented in a multitude of polaronic states leading, inevitably, to the failure of the electronic picture. The presented results lead to a critical revision of the state–of–the–art description of carbon–based nanostructures, opening a wealth of potential implications. PACS. 71.38.-k – 63.20.dk – 79.60.Fr , 78.20.-e