Atomic Structure

This is the most critical part of the input, defining the physical system you are simulating. You can provide this information by uploading a standard Crystallographic Information File (CIF), a Siesta XV file, or by entering the data manually.

• Lattice Vectors: Defines the size and shape of the periodic simulation cell in Angstroms. For molecules, use a large box to ensure no interaction between periodic images.
• ChemicalSpeciesLabel: Maps a species index to an atomic number and symbol. This is how Siesta knows which pseudopotential to use for each atom type.
• AtomicCoordinatesAndAtomicSpecies: Lists the Cartesian coordinates (in Angstroms) and the corresponding species index for every atom in the cell.