Molecular dynamics simulation of nanomanipulation based on AFM in liquid ambient

Environmental factor is one of the most fundamental parameters in analyzing nanorobots and nanoassemblies. This study focuses on analyzing the manipulation process in a liquid environment using molecular dynamics simulation method. For this purpose, extended simple point-charge water model has been used to model an aqueous media. The effects of different conditions such as substrate material, submerging, electrical charge, and adhesion have been investigated on the manipulation force. In the water media, performing the manipulation process can reduce the manipulation force and increase the possibility of manipulation on the substrates with high adhesion. The manipulation results illustrate that these forces have extremum values in dry (vacuum) and partially submerged nanomanipulations. When the manipulation is carried out in the aqueous media, the interaction of nanoparticle and substrate reduces and leads to decrease the damage of targeted nanoparticle. The RMS criterion confirms this result. The results indicate the adhesion and attraction forces between the tip and nanoparticle reduce in the aqueous media. This reason leads to occur no pulling mode manipulation in the water. Due to dipolar property of water molecules, charge plays a significant role in the manipulation for aqueous ambient. The comparison of manipulation results by charged and chargeless tip shows a larger manipulation force while the charged tip is used.