A Molecular-Dynamics Model On The Generation Of Glass SiO₂Nanochannel By Various Tensile Conditions

The research project derived from the National Key Basic Research Development Program (973Program)(2011CB707602); the National Natural Science Foundation (50975136,51275229).The nanofludic devices with the nanopores are the foundation of the third generation of the DNAsequencing technology. Compare with the traditional nanopores constructed on the nano films, thenanofludic devices made by the SiO2have higher stiffness, strength and stability. Preparing thenanopore of SiO2is a great challenge of the modern manufacturing. We study on the relevant basicscience issues and analyze the influence factors of manufacturing.Firstly, this paper introduces the development, basic concepts and methods of the moleculardynamics(MD) method. And then, A molecular dynamics model of the nano glass tube based on theperiodic boundary condition(PBC) is proposed. With this model, we simulate the relaxation processof the glass tube at a certain temperature(2000K). At last, the law of the tensile property underdifferent strain rates is measured by using the tersoff potential for Si-O system.The results show the stress-strain relationship of the glass tube below5nanometer generated byMD simulation. Then the variation of inner and outer diameter under different strain rates is revealed.Furthermore, the radial distribution function(RDF) of SiO2glass have been calculated. On the otherside, we study on the variation axial tension of under different temperature: the elastic stage of SiO2system increases with increasing temperature. After the tension failure of the glass tube, aphenomenon of necking was observed during the MD simulations. these results provide the theorybasis for practical manufacturing.