AB INITIO MOLECULAR DYNAMICS SIMULATIONS ON LOCAL STRUCTURE AND ELECTRONIC PROPERTIES IN LIQUID MgxBi1-x ALLOYS

The microscopic structure and dynamics of liquid Mg x Bi 1-x(x = 0.5, 0.6, 0.7) alloys together with pure liquid Mg and Bi metals were investigated by means of ab initio molecular dynamics simulations. We present results of structure properties including pair correlation function, structural factor, bond-angle distribution function and bond order parameter, and their composition dependence. The dynamical and electronic properties have also been studied. The structure factor and pair correlation function are in agreement with the available experimental data. The calculated bond-angle distribution function and bond order parameter suggest that the stoichiometric composition Mg 3 Bi 2 exhibits a different local structure order compared with other concentrations, which help us understand the appearance of the minimum electronic conductivity at this composition observed in previous experiments.

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The Effect of Pressure on the Hydrogen Bond Structure of Liquid Water

Zeitschrift für Naturforschung A ◽

10.1515/zna-1984-0211 ◽

1984 ◽

Vol 39 (2) ◽

pp. 179-185 ◽

Cited By ~ 41

Author(s):

G. Pálinkás ◽

P. Bopp ◽

G. Jancsó ◽

K. Heinzinger

Keyword(s):

Molecular Dynamics ◽

Hydrogen Bond ◽

Liquid Water ◽

Bond Angle ◽

Angle Distribution ◽

Structure Of Water ◽

Effect Of Pressure ◽

Bond Angle Distribution ◽

Dynamics Simulations ◽

Force Potential

The results of molecular dynamics simulations of low and high pressure liquid water using a modified central force potential have been analyzed in order to study the effect of pressure on the hydrogen bond structure of water. The properties investigated and discussed include the hydrogen bond angle distribution, the O -O distance distribution between the neighbour molecules, the structure of the first coordination sphere in the high density liquid and the average number of hydrogen bonds.

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AB INITIO MOLECULAR DYNAMICS SIMULATIONS ON LOCAL STRUCTURE AND ELECTRONIC PROPERTIES IN LIQUID Sb FROM 913 K TO 1193 K

International Journal of Modern Physics B ◽

10.1142/s0217979213500124 ◽

2013 ◽

Vol 27 (05) ◽

pp. 1350012 ◽

Cited By ~ 3

Author(s):

QING-HAI HAO ◽

Y. D. LI ◽

XIANG-SHAN KONG ◽

C. S. LIU

Keyword(s):

Molecular Dynamics ◽

Ab Initio ◽

Temperature Dependence ◽

Molecular Dynamics Simulations ◽

Order Parameter ◽

Bond Order ◽

Ab Initio Molecular Dynamics ◽

Wave Number ◽

Cluster Properties ◽

Dynamics Simulations

Ab initio molecular dynamics simulations on liquid Sb have been carried out at five different temperatures from 913 K to 1193 K. We have investigated the temperature dependence of structure properties including structural factor S(Q), pair correlation function g(r), bond-angle distribution function g3(θ), cluster properties and bond order parameter Q4 and Q6. A shoulder was reproduced in the high wave number side of the first peak in the S(Q) implying that the residual structure units of crystalline Sb remain in liquid Sb . There is a noticeable bend at around 1023 K in the temperature dependence of the first-peak height of S(Q), the cluster properties and bond order parameter Q4, respectively, indicating that an abnormal structural change may occur at 973–1023 K.

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THE CORRELATION BETWEEN BOND ANGLE DISTRIBUTION AND THE COORDINATION OF SILICA LIQUID UNDER PRESSURE

International Journal of Modern Physics B ◽

10.1142/s0217979212501172 ◽

2012 ◽

Vol 26 (20) ◽

pp. 1250117 ◽

Cited By ~ 1

Author(s):

L. T. VINH ◽

N. V. HUY ◽

P. K. HUNG

Keyword(s):

Experimental Data ◽

Molecular Dynamics ◽

Bond Angle ◽

Simple Expression ◽

Dynamics Simulation ◽

Angle Distribution ◽

Bond Angle Distribution ◽

Simulation Results ◽

Substantial Change ◽

Good Agreement

Molecular dynamics simulation is carried out for liquid SiO 2 at pressure ranged from zero to 30 GPa and by using BKS, Born–Mayer type and Morse–Stretch potentials. The constructed models reproduce well the experimental data in terms of mean coordination number, bond angle and pair radial distribution function. Furthermore, the density of all samples can be expressed by a linear function of fractions SiO x. It is found that the topology of units SiO x and linkages OSi y is unchanged upon compression although the liquid undergoes substantial change in its network structure. Consequently, the partial bond angle distribution for SiO x and OSi y is identical for all samples constructed by the same potential. This result allows to establishing a simple expression between total bond angle distribution (BAD) and fraction of SiO x and OSi y. The simulation shows a good agreement between the calculation and simulation results for both total O–Si–O and Si–O–Si BADs. This supports a technique to estimate amount of units SiO x and linkages OSi y on base of total Si–O–Si and O–Si–O BADs measured experimentally.

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Molecular Dynamics Simulation of Structural Changes of Ag965 Clusters during Freezing

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.683.348 ◽

2013 ◽

Vol 683 ◽

pp. 348-352

Author(s):

J.H. Xia ◽

Zheng Fu Cheng ◽

Xu Yang Xiao

Keyword(s):

Molecular Dynamics ◽

Structural Changes ◽

Pair Correlation ◽

Orientational Order ◽

Amorphous Structure ◽

Rapid Quenching ◽

Dynamics Simulation ◽

Angle Distribution ◽

Quenching Condition ◽

Dynamics Simulations

The structural transitions of Ag965clusters during two different quenching processes (Q1:1.0×1014K/s, Q2: 1.0×1012K/s) were studied using molecular dynamics simulations. This work gives the structure properties including the variations with temperature of pair-correlation function, bond-angle distribution function, bond pairs and bond orientational order parameters in both rapid quenching processes. Our results indicated that the liquid Ag965 was frozen into amorphous structure at 100 K under the quenching condition Q1. While the liquid Ag965transformed to hexagonal close-packed (hcp) phase at the temperature 100 K under the quenching condition Q2.These instructions give you basic guidelines for preparing papers for conference proceedings.

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Structure and Properties of the GeAsS Glasses from Ab initio Calculations

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1035.502 ◽

2014 ◽

Vol 1035 ◽

pp. 502-507

Author(s):

Li An Chen

Keyword(s):

Molecular Dynamics ◽

Molecular Dynamics Simulation ◽

Ab Initio ◽

Bond Angle ◽

Distribution Functions ◽

Dynamics Simulation ◽

Angle Distribution ◽

Structure And Properties ◽

Bond Angle Distribution ◽

Pair Distribution Functions

The structure and properties of the GexAsxS100-2x have been studied by ab initio molecular dynamics simulation. By calculating the pair distribution functions, bond angle distribution functions, we analyze the structure and properties of the alloys. Calculations show that Ge and As are all well combined with S atoms. When x is smaller than 25.0 the binding increases with x , when x is larger than 25.0 the binding decreases with increasing x . The intervention of As atom does not affect the GeS2 formation in Ge40As40S80

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Phase separation of Si1-xGex alloys

MRS Proceedings ◽

10.1557/proc-378-1031 ◽

1995 ◽

Vol 378 ◽

Cited By ~ 2

Author(s):

Eunja Kim ◽

Young Hee Lee

Keyword(s):

Molecular Dynamics ◽

Distribution Function ◽

Phase Separation ◽

Bond Angle ◽

Alloy System ◽

Order Parameters ◽

Angle Distribution ◽

Bond Angle Distribution ◽

Random Alloy ◽

Amorphous Si

AbstractWe generate liquid and amorphous Si1_xGex alloys for various Ge compositions using ab initio molecular dynamics approach. The electronic bonding characters and structural properties are discussed in terms of radial distribution function, bond angle distribution, and order parameters. Although the order parameters suggest approximately random alloy for all compositions, the snapshots reveal clearly phase separation. We will discuss how the phase can be separated in SiGe alloy system.

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Structural and Electronic Properties of Cu64Zr36 BMG by ab initio Molecular Dynamics

MRS Proceedings ◽

10.1557/opl.2012.1757 ◽

2013 ◽

Vol 1517 ◽

Cited By ~ 1

Author(s):

Jonathan Galván-Colín ◽

Ariel A. Valladares ◽

Alexander Valladares ◽

Renela M. Valladares

Keyword(s):

Metallic Glasses ◽

Pair Distribution Function ◽

Bond Angle ◽

Ab Initio Molecular Dynamics ◽

Vibrational Properties ◽

Angle Distribution ◽

Electronic Density ◽

Bond Angle Distribution ◽

Structural And Electronic Properties ◽

Radial Pair Distribution Function

ABSTRACTMuch attention has been given to bulk metallic glasses (BMG) in recent years, particularly those based on binary alloys due to the simplicity of their atomic composition. Although efforts to understand the atomistic features that give rise to their exceptional properties have been made, the electronic and vibrational properties have been disregarded. We undertook the task of simulating the Cu64Zr36 glassy metal using a supercell with 108 atoms and a different simulational approach: the undermelt-quench approach [1]. The structure was characterized by means of the radial (pair) distribution function and the bond-angle distribution and the electronic density of states was calculated. We find that our results agree well with experimental data.

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