Where relevant, these discussion are aided by graphical representations of the data, which are drawn using the Matplotlib library. This includes a graph of the total system energy plotted against each optimisation step gap (Figure ), which is useful for diagnosing convergence problems, a graph of the HOMO-LUMO and close-lying orbitals gap (Figure ), and a graph of the electronic excited-state energies (Figure ). Digichem is also capable of simulating UV-Vis absorption/emission, IR absorption and NMR spectra, by applying a Gaussian line-broadening function to the calculated electronic excited states, vibrational frequencies (Figure ) and/or NMR shielding parameters and coupling constants. In addition to these graphs, the Digichem calculation report sub-module can create three-dimensional renders of the molecular geometry (Figure ), which can be optionally augmented with a plot of the permanent dipole moment (Figure ) and/or a selected transition dipole moment (Figure ).