Gold/Benzenedithiolate/Gold Molecular Junction: A Driven Dynamics Simulation on Structural Evolution and Breaking Force under Pulling

Dynamic evolutions of molecular binding structures and breaking forces of gold/thiolate molecular junctions under pulling are still not well understood. We perform driven dynamics simulations to show that there are essentially two distinct breaking force traces corresponding to the Au–Au and Au–S bond ruptures. The latter is attributed to the formation and breaking of an additional “–Au–SR–Au–” unit in the molecular junction. The force histogram shows two force quanta at 1.5 and 2.0 nN, corresponding to the Au–Au and Au–S bond breaking. Our findings provide new molecular insights into the gold–thiolate interactions. The intermediate metal–molecule–metal binding structures could be used for further molecular transport calculations.