Siesta

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A Ruby script to call Siesta for simulations of molecules and solids.

Installation

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To use this project, follow these steps:

1. Clone the repository: Run git clone https://github.com/yachzh/ruby_siesta.git to download the project.
2. Get pseudopotentials: Run git clone https://github.com/yachzh/siesta_pseudo.git to obtain the pseudopotentials in psf format for Siesta.
3. Install dependencies: Ensure you have Ruby (version >= 2.6.8) and Siesta (version >= 4.1.5) installed on your system.
4. Set Ruby library path: Append the ruby_siesta/lib directory to the Ruby library path using export RUBYLIB=/path/to/ruby_siesta/lib.
5. Define pseudopotential path: Set the path to siesta_pseudo using export SIESTA_PP_PATH=path/to/siesta_pseudo.
6. Configure Siesta command: To run Siesta with 8 CPU cores, set the command to export RUBY_SIESTA_COMMAND="mpirun -np 8 siesta PREFIX.fdf > PREFIX.out".

Example Usage

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Here's an example of how to use the project:

# Import the Siesta module
require 'siesta'

# Create a new Siesta instance from a file
siesta = Siesta.import_from_file('input.STRUCT_OUT') # Supports *.STRUCT_OUT, *.vasp (*poscar*), *.xyz files

# Set the label for the simulation
siesta.label('silicon')

# Set the exchange-correlation functional
siesta.xc('PBE')

# Set the spin polarization
siesta.spin(pol: false)

# Set the k-point mesh
siesta.kpoint(kmesh: [9, 9, 9])

# Calculate the total energy
energy = siesta.energy

# Print the result
puts "Total energy: #{energy} eV" #=> Total energy: -214.148814 eV

Note

Make sure to replace /path/to/ruby_siesta/lib and /path/to/siesta_pseudo with the actual paths on your system.