Molecular dynamics simulations of the vibrational signature transfer from a glycine peptide chain to nanosized gold clusters

Molecular dynamics simulations are used to study a glycine polypeptide chain connected to gold nanoclusters. This system is used as a proof of concept for the development of scenarios for the transmission of signals encoded into molecular vibrations (vibronics) instead of the standard encoding in electron currents (electronics). We demonstrate theoretically that, although a linear polypeptide is not energetically stable thus not suitable to be connected to gold clusters, a prerelaxed polypeptide can stay connected to the nanosized gold electrodes showing a final stable structure, which is important for the design and development of molecular vibronics systems. The frequency analysis shows an observable change of the vibrational characteristics of the nanogold cluster due to the peptide presence, suggesting that such system can also be used as a sensor device for molecule detection.