Fully Atomistic Modeling of Carbon Quantum Dots in Aqueous Solution

We present the results of extensive multiensemble Molecular Dynamics simulations of triangular Graphene Quantum Dots (GQD’s) solvated in water at room temperature. We use energetics, structural quantities and autocorrelation functions in three different ensembles to provide insight into the nature of the behavior of systems comprised of 2 to 6 triangular graphene-like layers for both armchair (AM) and zigzag (ZZ) configurations of 54 to 168 carbon and 27 to 42 hydrogen atoms per layer. The individual layers remain very rigid even for the largest layers and there is a small amount of inter-layer spacing variation between different systems. Simulated Raman spectra capture a wide variety of normal modes in the system that are highly dependent on the structure under consideration, suggesting that Raman spectra can be used to experimentally distinguish between these. Results are in reasonable agreement with those calculated and observed in multilayer graphene systems.