The Study On Simulation Method Of Dielectric Constant Of Inorganic Materials

Dielectric is a kind of substance which can produce macroscopic non-zero electric dipole moment and electrically polarized reaction under the action of external electric field.Dielectric constant is an important index used to describe dielectric properties of dielectric materials.The permittivity can be directly measured experimentally at room temperature.However,in some actual working conditions,there may be a high temperature of thousands of degrees Celsius,and there are a series of problems such as material deformation and experimental equipment parameter change caused by high temperature phase transformation,so the experimental measurement method under high temperature conditions is seriously interfered by the external environment,and the operation is very difficult.Compared with the experimental method and computer simulation to facilitate visual research structure transformation process of high temperature material,and in the process of simulation calculation on the basis of the principle of physics material dielectric constant at different temperatures,can make up for the lack of experimental observation,at the same time can carry on the effective control to the complex and changeable external environment to complete a series of experiments are unfavorable.Therefore,computer simulation has become one of the key technologies to study the electromagnetic properties of materials at different temperatures.The development of the simulation calculation method of material dielectric constant not only provides a good theoretical guidance for material design,but also saves a lot of manpower,material and financial resources,and can realize efficient and accurate virtual screening.It is of great significance to study the phenomenon and motion of electric polarization of bound charge in dielectric under the action of temperature and electric field,to analyze the relationship between dielectric structure and electric polarization law,to discover the micro mechanism of dielectric macroscopic dielectric properties,and to study the calculation and simulation method of dielectric properties for the development of the utility of dielectric.In this work,the dielectric response theory and molecular dynamics simulation are combined to study the electromagnetic properties of materials at different temperatures and concentrations by means of computer simulation.Mainly through the following steps to achieve the calculation of dielectric material dielectric constant,first of all,based on the basic theory of electrodynamics,the relationship between the dipole moment and dielectric constant is established;And then use the statistical mechanics parameters obtained from molecular dynamics simulation to the electrostatic field in the dielectric permittivity of correlation model again through the partition function,obtain statistically dipole moment dipole moment of contact with the dielectric constant fluctuation method,and through the applied electric field and electric field direction of the dipole moment relations directly derived method of dielectric constant of the applied electric field.Finally,the above two methods are used to study the dielectric properties of pure water,sodium chloride crystal and sodium chloride aqueous solution.By comparing with experimental data,the feasibility and accuracy of molecular dynamics simulation to calculate the dielectric properties of materials in various states are further verified.