Units of excited state energies

[danielhollas]

Just tested a TDDFT calculation with ORCA 4.2.0 The excited state energies and oscillator strengths are present in the output dict, but the excited state energies are in rather arbitrary units of cm^-1. I wonder if we shouldn't change the units to something saner, either eV or a.u. to make it consistent with the SCF energy. Also of note that these are energies relative to the ground state (which is fine). I guess this might be a bigger discussion about units...

btw: This package might be interesting for manipulating units.

[danielhollas]

If we want to play with units, we should do that before releasing stable version. It would be nice to see what other plugins are doing. Also we need to check actually how cclib handles units and whether they are consistent at least (e.g. if all excited state methos are in cm^-1 or not).