Welcome

This isn't an ordinary video editing. It's a molecular dynamic simulation's visualisation. Here I have made Mono Hydrogen(H) atoms to vibrate. Sounds interesting right! This is a very simple simulation, and you can do it easily. But before doing that you need to understand the software. Don't worry if you don't know. Keep visiting the blog so that you can learn easily.

Software used: LAMMPS

Visualisation done on: OVITO

If you are interested in the above simulation and you want your name to be displayed like that, contact me through E-Mail mentioning the text which you want to display. Keep the text short so that I can generate the simulation as earlier as possible.

Molecular static simulation of Argon gas

Input script

#-------------------------------------------------------------------------------------------------------------------------

units metal #What are the units you will use to specify various things in the input file? 

boundary p p p #<Specify periodic boundary condition are needed in all three faces of the simulation box> 

atom_style atomic #<What style of atoms is to be used in the simulation>

log logfile.txt #<Write the log file to this text file. All thermodynamic information is applicable to the entire system>

Molecular dynamics simulation of Argon gas

Input script

#-------------------------------------------------------------------------------------------------------------------------

units metal #What are the units you will use to specify various things in the input file?
boundary p p p #Specify periodic boundary condition are needed in all three faces
atom_style atomic #What style of atoms is to be used in the simulation
log logfile.txt #Write the log file to this text file. All thermodynamic information applicable to the entire system
#================================================
region forbox block 0 45.8 0 45.8 0 45.8 units box
#Refers to an abstract geometric region of space. units box refers to the fact that the size of the box is specified in the units as given in the units command. The name "forbox" refers to the region ID so that you can refer to it somewhere else in this input script.
create_box 1 forbox #Create the box

Basic Nickel simulation

Input script

units metal #<What are the units you will use to specify various things in the input file?
boundary p p p #<Specify periodic boundary condition are needed in all three faces of the simulation box>
atom_style atomic #<What style of atoms is to be used in the simulation>
log logfile.txt #<Write the log file to this text file. All thermodynamic information applicable to the entire system>
#================================================
region forbox block 0 35.2 0 35.2 0 35.2 units box
#<Refers to an abstract geometric region of space. units box refers to the fact that the size of the box is specified in the units as given in the units command. The name "forbox" refers to the region ID so that you can refer to it somewhere else in this input script.>
create_box 1 forbox #<Create the box>

Verifying lattice constant-Nickel

Lattice constant for Nickel is 3.52 angstrom. But how do we know it is correct? There is a computational technique using which we can verify the lattice constant values. Let's see how.

Generally, every atom, molecule, crystal whatever it is, tend to have the lowest potential energy state, possible for that. That's nature. This potential energy of atoms depends directly on the lattice constant corresponding to its crystal structure. So the crystal will have lattice constant which corresponds to the lowest potential energy. Here I am going to calculate the potential energy of nickel for various lattice constants. 

Nickel sphere collision

In this blog, I have made a simulation on which two nickel spheres colloid each other. Through this simulation, I have introduces some new commands. Have a look at them.

Input script

#------------------ Setup the simulation -------------------------
log                   log.in
dimension       3
units                metal
atom_style      atomic
boundary         p p p

Plotting stress strain curve for gold

In this blog, I am showing a method using which stress-strain curve can be plotted for any given metal. I am using gold as an example here. 

Input script

units           metal
atom_style      atomic
boundary        p p p
#FCC unit cell
variable a index 4.0782

Finding elastic constants for Gold using molecular dynamics method

Continuing my previous blog here I will be showing how to calculate elastic constants of metals (illustrating gold as an example here). As stated earlier, 2 separate simulations will be performed in order to calculate the elastic constants.

Input script-Simulation 1 (for calculating C_11, C₁₂ )

                   (Tensile loading condition)

units           metal
atom_style      atomic
boundary        p p p

Crack initiation in molecular dynamics

 In this blog, I will be showing how to initiate a crack in the molecular dynamics method. For this, I am using aluminium as an example.

Input script

####distance-amstrongs,mass-gram/mole

units metal 

boundary s s p 

atom_style atomic 

neighbor        0.3 bin

neigh_modify    delay 5

Polymer simulation

In this blog, I will be showing how to calculate the Radius of gyration and Radial distribution function(rdf) for a polymer chain.

 Input script

# VARIABLES

variable fname index PE_cl100.txt

variable simname index PE_cl100