Unit Cell Files
vampire provides a selection of built-in unit cell crystal structures which can be specified with the
create:crystal-structure keyword. However, there are many more crystal structures and magnetic materials than the code could possibly support, and so an advanced mode is available where the user can specify any atomic structure and exchange interactions which are then imported into the code and can be used to generate large systems and/or cut into the standard geometric shapes. It is also possible to simulate complex non-periodic structures such as nanoparticles obtained from molecular dynamics simulations with the same approach. The unit cell file is specified in the main input file using the keyword:
material:unit-cell-file = file.ucf
where "file.ucf" is the filename
To learn about the The unit cell file format check the user manual in the page 22 at the following link: https://vampire.york.ac.uk/resources/vampire-manual.pdf
input
#------------------------------------------
# Sample vampire input file to perform
# benchmark calculation for v4.0
#
#------------------------------------------
#------------------------------------------
# Creation attributes:
#------------------------------------------
#create:crystal-structure=sc
create:periodic-boundaries-x
create:periodic-boundaries-y
#create:periodic-boundaries-z
#------------------------------------------
# System Dimensions:
#------------------------------------------
dimensions:unit-cell-size = 1.0 !A
dimensions:system-size-x = 0.7 !nm
dimensions:system-size-y = 0.7 !nm
dimensions:system-size-z = 0.7 !nm
#------------------------------------------
# Material Files:
#------------------------------------------
material:file = Co.mat
material:unit-cell-file = Co.ucf
#------------------------------------------
# Simulation attributes:
#------------------------------------------
sim:temperature = 300.0
sim:time-steps-increment = 1000
sim:total-time-steps = 10000
sim:time-step = 1 !fs
#------------------------------------------
# Program and integrator details
#------------------------------------------
sim:program = benchmark
sim:integrator = llg-heun
#------------------------------------------
# data output
#------------------------------------------
output:real-time
output:magnetisation
screen:time-steps
screen:magnetisation-length
Co.mat
#===================================================
# Sample vampire material file V5
#===================================================
#---------------------------------------------------
# Number of Materials
#---------------------------------------------------
material:num-materials=1
#---------------------------------------------------
# Material 1 Cobalt Generic
#---------------------------------------------------
material[1]:material-name=Co
material[1]:damping-constant=1.0
material[1]:exchange-matrix[1]=11.2e-21
material[1]:atomic-spin-moment=1.72 !muB
material[1]:second-order-uniaxial-anisotropy-constant=1.0e-24
material[1]:material-element=Ag
material[1]:minimum-height=0.0
material[1]:maximum-height=1.0
Co.ucf
# Unit cell size:
3.54 3.54 3.54
# Unit cell vectors:
1.0 0.0 0.0
0.0 1.0 0.0
0.0 0.0 1.0
# Atoms num, id cx cy cz mat lc hc
1
0 0.5 0.5 0.5 0 1 2
# Interactions n exctype, id i j dx dy dz Jij
6 isotropic
0 0 0 1 0 0 11.2e-21
1 0 0 -1 0 0 11.2e-21
2 0 0 0 1 0 11.2e-21
3 0 0 0 -1 0 11.2e-21
4 0 0 0 0 1 11.2e-21
5 0 0 0 0 -1 11.2e-21
Calculation
/vampire-tutorials/Co> vampire-serial
_
(_)
__ ____ _ _ __ ___ _ __ _ _ __ ___
\ \ / / _` | '_ ` _ \| '_ \| | '__/ _ \
\ V / (_| | | | | | | |_) | | | | __/
\_/ \__,_|_| |_| |_| .__/|_|_| \___|
| |
|_|
Version 6.0.0 Apr 26 2022 23:42:26
Git commit:
Licensed under the GNU Public License(v2). See licence file for details.
Lead Developer: Richard F L Evans <richard.evans@york.ac.uk>
Contributors: Sarah Jenkins, Andrea Meo, Andrew Naden, Matthew Ellis,
Oscar Arbelaez, Sam Morris, Rory Pond, Weijia Fan,
Phanwadee Chureemart, Pawel Sobieszczyk, Joe Barker,
Thomas Ostler, Andreas Biternas, Roy W Chantrell,
Wu Hong-Ye, Razvan Ababei, Sam Westmoreland,
Daniel Meilak
Compiled with: GNU C++ Compiler
Compiler Flags:
Vampire includes a copy of the qhull library from C.B. Barber and The
Geometry Center and may be obtained via http from www.qhull.org.
================================================================================
Fri May 6 00:09:30 2022
================================================================================
Initialising system variables
Creating system
Generating neighbour list..........done!
Copying system data to optimised data structures.
Using generic/normalised form of exchange interaction with 6 total interactions.
Number of atoms generated: 10648
Starting Simulation with Program Benchmark...
1000 0.887306
2000 0.888853
3000 0.897749
4000 0.890028
5000 0.889241
6000 0.893616
7000 0.890793
8000 0.890163
9000 0.887654
10000 0.892783
Simulation run time [s]: 19.6266
Simulation ended gracefully.
The content of the output file
#----------------------------------------------------------------------------------------------------------------------------------------------------------
# Output file for vampire simulation
# time : 2022-05-06 00:09:31 process id : 3775
# hostname : linux-kq57
# path : /home/algerien/abinitio/vampire-tutorials/Co
# version : 6.0.0
# githash :
#----------------------------------------------------------------------------------------------------------------------------------------------------------
1e-12 0.115414 -0.00861624 0.99328 0.887306
2e-12 0.2 -0.035775 0.979143 0.888853
3e-12 0.156644 -0.0751085 0.984795 0.897749
4e-12 0.195622 -0.131047 0.971884 0.890028
5e-12 0.336083 -0.0791647 0.938499 0.889241
6e-12 0.29656 -0.0194227 0.954817 0.893616
7e-12 0.261457 -0.162865 0.951375 0.890793
8e-12 0.203677 -0.220226 0.953948 0.890163
9e-12 0.270237 -0.293326 0.917023 0.887654
1e-11 0.274289 -0.22906 0.933969 0.892783
Hello, my name is Dr Abderrahmane Reggad. I'm a 51 year old and I am a researcher in materials' sciences. 
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