A sample CASTEP run

Whether you perform a single-point energy calculation, minimize a structure, run a molecular dynamics simulation, calculate elastic constants, or perform a transition-state search, the sequence of steps that is executed to run a remote CASTEP job is always the same. When you click the Run button on the CASTEP Calculation dialog, the steps described in A sample remote job run happen with the following differences:

For Energy calculations, if

Update structure is checked: there is no effect, as no structural changes are associated with this task.
Update graphs is checked: Materials Studio creates a chart document called [seedname] Energies.xcd, showing the total energy versus SCF iteration, and another chart document called [seedname] Convergence.xcd, showing, on the logarithmic scale, the convergence of the total energy versus SCF iteration.
Update textual results is checked: Materials Studio downloads a text file called Status.txt that contains a summary of the calculation performed (task, DFT functional, energy cutoff for plane wave basis set, electronic minimization method, system charge and spin, and so on), the SCF iteration number, the total energy, and the total energy convergence (that is, the change from the previous iteration).

For Geometry Optimization calculations, if

Update structure is checked: Materials Studio downloads a snapshot of the structure and modifies a copy of the original structure accordingly.
Update graphs is checked: Materials Studio creates a chart document called [seedname] Energies.xcd, showing the total energy versus optimization step, and another chart document called [seedname] Convergence.xcd, showing, on the logarithmic scale, the total energy change, the maximum displacement, the maximum force, and the maximum stress versus optimization step.
Update textual results is checked: Materials Studio downloads a text file called Status.txt that contains a summary of the calculation performed (task, DFT functional, energy cutoff for plane wave basis set, electronic minimization method, system charge and spin, and so on), the SCF iteration number, the total energy, the total energy convergence (that is, the change from the previous iteration), the maximum displacement, the maximum force, and the maximum stress for the last completed optimization step.

For Dynamics calculations, if

Update structure is checked: Materials Studio downloads a snapshot of the structure and modifies a copy of the original structure accordingly.
Update graphs is checked: Materials Studio creates a chart document called [seedname] Constant.xcd, showing the constant of motion versus simulation time, and another chart document called [seedname] Temperature.xcd, showing the temperature versus simulation time. In addition, the chart document [seedname] Pressure.xcd is created if the calculation is run using the NPH or NPT ensembles.
Update textual results is checked: Materials Studio downloads a text file called Status.txt that contains a summary of the calculation performed (task, DFT functional, energy cutoff for plane wave basis set, electronic minimization method, system charge and spin, and so on), the number of completed dynamics steps, the temperature, and the constant of motion for the last completed optimization step.

For Elastic Constants calculations, if

Update structure is checked: there is no effect, as no structural changes are associated with the original structure. CASTEP performs an Energy calculation for the initial structure.
Update graphs is checked: Materials Studio creates a chart document called [seedname] Energies.xcd, showing the total energy versus optimization step, and another chart document called [seedname] Convergence.xcd, showing, on a logarithmic scale, the total energy change, the maximum displacement, and the maximum force versus optimization step. These charts refer to the structure currently being processed, as indicated by the index of the strain pattern and of the strain magnitude for that pattern.
Update textual results is checked: Materials Studio downloads a text file called Status.txt that contains a summary of the calculation performed (task, DFT functional, energy cutoff for plane wave basis set, electronic minimization method, system charge and spin, and so on), a description of the structure currently being processed (as indicated by the index of the strain pattern and of the strain magnitude for that pattern), the number of completed optimization steps, the total energy, and the total energy convergence (that is, the change from the previous iteration), the maximum displacement, and the maximum force for the last completed optimization step.

For TS Search calculations, if

Update structure is checked: Materials Studio downloads a snapshot of the structure and modifies a copy of the original structure accordingly.
Update graphs is checked: Materials Studio creates a chart document called [seedname] TSSearch.xcd, showing the total energy versus reaction coordinate. For each phase of the transition-state search, a separate graph is displayed within the chart document.
Update textual results is selected: Materials Studio downloads a text file called Status.txt that contains a summary of the calculation performed (task, DFT functional, energy cutoff for plane wave basis set, electronic minimization method, system charge and spin, and so on), a description of the phase of the transition-state search currently being processed, the reaction path coordinate, the total energy, the total energy convergence (that is, the change from the previous iteration), the maximum displacement, and the maximum force for the last completed search step.

For Properties runs or for any other task where electronic structure properties (band structure, density of states, or optical properties) are requested, textual updates are modified as follows.

When the CASTEP run enters the properties stage, the task description in the Status.txt file is changed to either Eigenvalues (for band structure or density of states) or Eigenvalues + Optical Properties (for optical properties). This file now contains a summary of the calculation, the number of completed non-self-consistent iterations of the eigenvalues calculation, the maximum convergence of electronic energies, and the maximum change in electronic energies on the last completed iteration for any band or k-point.

Once the job has finished, Materials Studio will transfer the output files back to your PC, where you can view and edit them, analyze the results, or use them for further calculations. Additional output files may be generated or modified depending on the type of calculation you performed.

For Energy runs, Materials Studio downloads all the CASTEP output files.
For Geometry Optimization runs, Materials Studio downloads all the CASTEP output files, updates the structure it has copied into the results folder to show the final geometry, and creates a trajectory file, [seedname].xtd, that contains the history of the optimization process. The trajectory file can be animated using the tools on the Animation toolbar.
For Dynamics runs, Materials Studio downloads all the CASTEP output files, updates the structure it has copied into the results folder to show the configuration at the beginning of the dynamics run, and creates a trajectory file, [seedname].xtd, that describes the molecular dynamics calculation. The trajectory file can be animated using the tools on the Animation toolbar.
For Elastic Constants runs, Materials Studio downloads all the CASTEP output files for all strain patterns and strain amplitudes.
For TS Search runs, Materials Studio downloads all the CASTEP output files, updates the structure it has copied into the results folder to show the resulting configuration, and creates a trajectory file, [seedname] .xtd, that contains the history of the optimization process. The trajectory file can be animated using the tools on the Animation toolbar.

A sample CASTEP run

See Also: