The CASTEP Energy task allows you to calculate the total energy of the specified 3D periodic system, as well its physical properties.
In addition to the total energy, the forces on atoms are reported at the end of the calculation. A charge density file is also created, allowing you to visualize the spatial distribution of the charge density using the Materials Visualizer. The electronic energies at the Monkhorst-Pack k-points used in the calculation are also reported, so that you can generate a density of states chart during CASTEP analysis.
The Energy task is useful for studying the electronic properties of systems for which reliable structural information is available. It can also be used to calculate an equation of state (i.e. a pressure-volume and/or energy-volume dependence) for high-symmetry systems with no internal degrees of freedom, as long as the Stress property is specified.
In systems with internal degrees of freedom, the equation of state can be obtained using the Geometry Optimization task.
The default unit of energy in CASTEP is the electron-Volt (eV). The relationship between eV and other popular energy units are found in Mohr et al., 2008:
|1 eV||0.0367493254 Ha||23.0605 kcal/mole||96.4853 kJ/mole|
Setting up CASTEP calculations
Analyzing CASTEP results