Tutorial

In order to begin a ground state search, we need a template scf file that will be used to fill out most of the input parameters. An example for MnO can be found in the test/assets/ subdirectory.

Creation

Once you have such a file for your case (or if you just want to try with MnO), execute:

cd ~/.julia/dev/RomeoDFT
romeo searcher create MnO_tutorial test/assets/MnO_scf.in --sleep-time 5

the sleep-time flag is used to specify how often the orchestrator polls for new results etc.

In this case, the structure definition will also be taken from the template file. If you want to use a different pw.x input or cif file from which to extract the structure, you can use

romeo searcher create MnO_tutorial test/assets/MnO_scf.in -s <structure_file> --sleep-time 5

There will be an interactive menu to further set up the Searcher, after which it will be started by the Orchestrator.

For further information on the searcher create command you can run

romeo searcher create -h

Monitoring

To get an overview of all the loaded Searchers you can execute

romeo orchestrator status

To view information of a specific Searcher, execute:

romeo searcher status <name>

where <name> in our case would be MnO_tutorial.

Stopping/Starting

To stop a running Searcher you can execute:

romeo searcher stop <name>

and to restart it

romeo searcher start <name>

If no Searcher with name was loaded yet, it will be first.

Changing mode

By default a Searcher will start in the search mode. This means that it is actively exploring the energy landscape in order to find unique metastable states. It will continue to do so until the amount of unique states versus trials goes below the value set with the unique-ratio flag during romeo searcher create. Afterwards, it will switch to the postprocess mode, meaning that it will not generate new trials, but simply process all the remaining trials and finish all the pending calculations. If the ratio of unique/trial happens to exceed the unique-ratio value after finishing the postprocessing, the mode will switch back to search.

Sometimes, however, it is desirable to manually switch the mode in order to limit the search or simply stop a searcher from exploring further but cleaning up everything. This can be done using:

romeo searcher mode <name> <mode>

See Modes for more info.

Plot States

An overview of the different states that are found so far can be plotted using

romeo searcher plot <name> <outfile>

which will produce an image and save it to outfile displaying the states.

Other commands

See CommandLine for more commands.