Molecular Dynamics Study of the Lattice Vibration Contribution to the Frequency-Dependent Dielectric Constant of Lithium Iodide

1990 ◽  
Vol 210 ◽  
Author(s):  
J. Deppe ◽  
M. Balkanski ◽  
R. F. Wallis ◽  
A. McGurn
Keyword(s):  
Molecular Dynamics ◽  
Isothermal Compressibility ◽  
Lattice Vibration ◽  
Lattice Energy ◽  
Dynamics Simulation ◽  
Optical Mode ◽  
Lithium Iodide ◽  
Current Correlation ◽  
Higher Temperature ◽  
Absorption And Dispersion

AbstractA molecular dynamics simulation has been performed on the crystal lithium iodide, LiI. A rigid ion potential was used with parameters fit to thermal expansion, isothermal compressibility, lattice energy and the frequency of the transverse optical mode at the zone center. The current-current correlation function has been calculated at T = 200K and 400K, and from this the absorption and dispersion have been obtained. Anharmonic broadening is observed at the higher temperature.

Molecular Dynamics simulation of organic materials: Structure, potentials and the MiCMoS computer platform

CrystEngComm ◽  
2022 ◽  
Author(s):  
Angelo Gavezzotti ◽  
Leonardo Lo Presti ◽  
Silvia Rizzato
Keyword(s):  
Molecular Dynamics ◽  
Molecular Dynamics Simulation ◽  
Structure Determination ◽  
Organic Materials ◽  
Single Point ◽  
Lattice Energy ◽  
Dynamics Simulation ◽  
Organic Crystals ◽  
X Ray ◽  
Point Lattice

The science of organic crystals and materials has seen in a few decades a spectacular improvement from months to minutes for an X-ray structure determination and from single-point lattice energy...

Molecular Dynamics Simulation of the Influence Factors of Particle Depositing on Surface during Cold Spray

2013 ◽  
Vol 652-654 ◽  
pp. 1916-1924 ◽  
Author(s):  
Hong Gao ◽  
Chao Liu ◽  
Fen Hong Song
Keyword(s):  
Molecular Dynamics ◽  
Molecular Dynamics Simulation ◽  
Crystalline Structure ◽  
Influence Factors ◽  
Deposition Process ◽  
Dynamics Simulation ◽  
Effective Combination ◽  
Material Hardness ◽  
Higher Temperature ◽  
Soft Cluster

Using molecular dynamics simulation, the influence factors of deposition process, such as cluster incident velocity, material hardness and so on, were studied. The cluster incident velocity influences the combination strength between the substrate and cluster greatly. The higher the cluster velocity is, the stronger the combination strength is, and the faster the cluster forms the crystalline structure like the substrate. Higher temperature of the substrate and the cluster will improve the combination strength. The size of the cluster influences the effect of combination as well. The larger the cluster is, the stronger the combination strength is. If a soft cluster impacts on a hard substrate, because of lack of enough deformation at the interface of the substrate, it is difficult to form the effective combination. If a hard cluster impacts on a soft substrate, the lattice defects occur and the cluster takes a longer time to form crystalline structure.

Molecular dynamics simulation of lithium iodide in liquid dimethylsulfoxide

2005 ◽  
Vol 401 (1-3) ◽  
pp. 217-222 ◽  
Author(s):  
Usa Onthong ◽  
Tünde Megyes ◽  
Imre Bakó ◽  
Tamás Radnai ◽  
Kersti Hermansson ◽  
...  
Keyword(s):  
Molecular Dynamics ◽  
Molecular Dynamics Simulation ◽  
Dynamics Simulation ◽  
Lithium Iodide

Molecular Dynamics Simulation of Normal and Explosive Boiling on Nanostructured Surface

2013 ◽  
Vol 135 (12) ◽  
Author(s):  
Hamid Reza Seyf ◽  
Yuwen Zhang
Keyword(s):  
Thin Film ◽  
Molecular Dynamics ◽  
Evaporation Rate ◽  
Solid Wall ◽  
Molecular System ◽  
Spherical Shape ◽  
Dynamics Simulation ◽  
Spherical Particles ◽  
Explosive Boiling ◽  
Higher Temperature

Molecular Dynamics (MD) simulation is carried out to investigate the normal and explosive boiling of thin film adsorbed on a metal substrate whose surface is structured by an array of nanoscale spherical particles. The molecular system is comprised of the liquid and vapor argon as well as a copper wall. The nanostructures have spherical shape with uniform diameters while the thickness of liquid film is constant. The effects of transvers and longitudinal distances as well as the diameter of nanoparticles are analyzed. The simulation is started from an initial configuration for three phases (liquid argon, vapor argon and solid wall); after equilibrating the system at 90 K, the wall is heated suddenly to a higher temperature that is well beyond the critical temperature of argon. Two different superheat degrees are selected: a moderately high temperature of 170 K for normal evaporation and much higher temperature 290 K for explosive boiling. By monitoring the space and time dependences of temperature and density as well as net evaporation rate, the normal and explosive boiling process on a flat surface with and without nanostructures are investigated. The results show that the nanostructure has significant effect on evaporation/boiling of thin film. The degrees of superheat and size of nanoparticles have significant effects on the trajectories of particles and net evaporation rate. For the cases with nanostructure, liquid responds very quickly and the number of evaporation molecules increases with increasing the size of particles from 1 to 2 nm while it decreases for d = 3 nm.

Perturbation Molecular Dynamics Simulation of Thermal Conductivity of Zirconia

2008 ◽  
Vol 368-372 ◽  
pp. 1325-1327
Author(s):  
Feng Zhang ◽  
Qun Bo Fan ◽  
Fu Chi Wang ◽  
Hui Ling Zhang
Keyword(s):  
Thermal Conductivity ◽  
Molecular Dynamics ◽  
Ceramic Materials ◽  
Dynamics Simulation ◽  
Pure Zirconia ◽  
Different Temperatures ◽  
Conductivity Curve ◽  
Higher Temperature ◽  
Thermal Conductivity Calculation ◽  
Dynamics Method

Thermal conductivity of zirconia and yttrium stabilized zirconia (YSZ) is calculated with perturbation molecular dynamics method (PMD). The results showed that thermal conductivity of YSZ is lower than that of pure zirconia and PMD is a very effective way in thermal conductivity calculation for ceramics. In higher temperature region, the calculated values show a different tendency with the experiment ones, which is because that photon conduction is not considered in PMD method. By taking photon effects into account, the calculated thermal conductivity curve is found fairly well coherent with measurements. In addition, the thermal expansion of zirconia is also presented by calculating the volumes at different temperatures. The results and methods in this paper have been proved to be very helpful in further design of new ceramic materials in the field of thermal barrier coatings (TBCs).

Thermal Conductivity of Carbon Nanotubes With Stone-Wales Defects

2009 ◽  
Author(s):  
Wei Li ◽  
Yanhui Feng ◽  
Jia Peng ◽  
Xinxin Zhang
Keyword(s):  
Thermal Conductivity ◽  
Carbon Nanotubes ◽  
Molecular Dynamics ◽  
Phonon Scattering ◽  
Dynamics Simulation ◽  
Linear Temperature ◽  
Bond Order Potential ◽  
Higher Temperature ◽  
Non Equilibrium Molecular Dynamics ◽  
Thermostat Model

Thermal conductivity of (5,5) and (3,3) carbon nanotubes with Stone-Wales (SW) defects is investigated by molecular dynamics simulation. Non-equilibrium molecular dynamics method is employed and the reactive empirical bond order potential is chosen. In the simulation, the temperature difference is given by applying the Berendsen thermostat model to each end of carbon nanotubes (CNTs). The thermal conductivity is calculated by Fourier’s equation. Different from linear temperature distribution along the tube for perfect CNTs without defects, there is temperature jump at defects for CNTs with a SW defect. The defect acts as additional phonon scattering centers and result in a local higher temperature gradient, which leads to a higher resistance to heat flow across the defect and thus a reduction in the thermal conductivity of the tube. The rotation angle of a SW defect barely influences the thermal conductivity of the tube. Probably, the thermal conductivity of CNTs with SW defects is more sensitive to the defect concentration than the defect distribution.

Molecular Dynamics Simulation of Diffusion Behavior for Thermalplastic Fusion Bonding

2011 ◽  
Vol 217-218 ◽  
pp. 45-50 ◽  
Author(s):  
Yi Bo Sun ◽  
Yi Luo ◽  
Xiao Dong Wang ◽  
Yu Qi Feng
Keyword(s):  
Molecular Dynamics ◽  
Molecular Level ◽  
Dynamics Simulation ◽  
Level System ◽  
Micro Electro Mechanical Systems ◽  
Diffusion Behavior ◽  
Fusion Bonding ◽  
Micro Assembly ◽  
Heating And Cooling ◽  
Higher Temperature

As a convenient way for the assembly of thermal plastic MEMS (Micro Electro-Mechanical Systems) devices fusion bonding was studied in molecular level. The diffusion behavior of polymer molecular chains was simulated by molecular dynamics. Amorphous PMMA (poly methyl methacrylate) layer were constructed. The interaction of PMMA layers in heating and cooling stages were simulated in NPT ensemble. In the simulation the PMMA molecular chains spread across the interface and entangled with the chains in the other layers. The factors including pressure and temperature which play important role in fusion bonding were analyzed in molecular level. System deformation was recorded in heating and cooling progress. Diffusion depth and binding energy in the model which had experienced heating and cooling simulation were obtained to investigate fusion degree. Deformation and fusion degree increase with larger pressure and higher temperature imposed to the system. It is concluded that only considering the diffusion of molecular chains parameters of relatively small pressure and high temperature are necessary to obtain precise bonding for micro joint, which is significant in guiding the precise bonding for micro assembly.

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