Increase electronic temperature for Fermi smearing when using xTB

[marcelmbn]

Electronic temperature

Increasing the electronic temperature used for Fermi smearing (fractional occupation according to Fermi statistics) might improve the convergence in electronically challenging and less defined cases during early optimization steps with xtb.

[marcelmbn]

I'd say that this would be a valuable extension and probably very easy to implement (we just have to connect the CLI command and toml entry with the flag for the xtb calculation).
Would you like to look into this, @jonathan-schoeps?

[jonathan-schoeps]

Yes i can have a look into this.