Run a MgO wavefunction calculation

In this exercise you will calculate the wavefunction of an MgO crystal by loading a CRYSTAL input file: MgO.inp

Starting DLVisualize

Open a terminal - right mouse click on the background, select New Terminal
In the terminal run the command source /opt/chemistry/crystal/3year_lab_setup
This sets up the environment you need to use DLViz
type dlv to start DLViz

Run a CRYSTAL calculation:

Calculate->CRYSTAL->Run SCF Input file
Click on Browse
Select MgO.inp
Select OK
Select OK

The Job List panel will open automatically and look something like this;

Select the job and the status line should report "Job has completed" - like this;

Click on Recover Files.

A model of MgO should have appeared in the DLV 3DView window.
This structure should look reasonably familiar it is the rocksalt lattice - with oxygen ions (red) and magnesium ions (green) drawn at their ionic radii.

Take a moment to familiarise yourself with DLV ...

On main panel the square icons are toggles which control how the 3D structure is displayed. A help message is displayed when you pass the mouse over each button. At first you are in rotate mode and can spin the structure by dragging with the right mouse button. Try changing to scale mode and translate mode etc.

Open the Structure Display panel

Display->Structure

Try out the controls on this panel - you can change the size of the atoms, display bonds, multiple unit cells etc etc.

Turn on label lattice to see the a, b and c lattice vectors labels.

The same lattice may also be described:

by a crystallographic (conventional) cell which is a cube of side 4.212 Angstrom (the lattice constant) and better reflects the true symmetry of MgO,
or by a primitive unit cell, whose vectors form a rhombohedron of side 2.9783 Angstrom and internal angle 60 degrees.

You can see the two cells using the Display->Structure panel.
Turn on draw lattice and select either Primitive or Conventional as the cell type.
You can build the lattice of MgO by repeating either cell.

Use the na, nb and nc sliders on the Display->Structure panel to draw multiple cells.

Give the current model a suitable name. This will be used as the label for this model in subsequent CRYSTAL simulations.

Edit -> Model -> Name
Change "Model_1" to something suitable; say "MgO".

Note:

For the change to take effect you must press Return.
You'll see the name of the graphics window change to "DLV 3DView - MgO";

A second window will open displaying the output from the CRYSTAL calculation (the LogFile).

It should look something like MgO.txt

Take some time to read through the LogFile.

Which is the hamiltonian/method adopted in the calculation?

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