Transport properties of the H2O@C60-dimer-based junction

Theoretical predictions play an important role in finding potential applications in molecular electronics. Fullerenes have a number of potential applications, and the charge flow from a single C-60 molecule to another becomes more versatile and more interesting after doping. Here, we report the conductance of two H2O@C-60 molecules in series order and how the number of encapsulated water molecules influences the transport properties of the junction. Encapsulating an H2O molecule into one of the C-60 cages increases the conductance of the dimer. Negative differential resistance is found in the dimer systems, and its peak-to-valley current ratio depends on the number of encapsulated H2O molecules. The conductance of the C-60 dimer and the H2O@C-60 dimer is two orders of magnitude smaller than that of the C-60 monomer. Furthermore, we demonstrate that the conductance of the molecular junctions based on the H2O@ C-60 dimer can be tuned by moving the encapsulated H2O molecules. The conductance is H2O-position dependent. Our findings indicate that H2O@C-60 can be used as a building block in C-60-based molecular electronic devices and sensors.