Excited state optimization failed in turbomole ( small HOMO LUMO gap )

[ylniu]

Dear all,

    Egrad calculation failed in optimization of excited state structure. I used eiger command to get the MO energies:

    81.    81 a                           -0.152002 H =        -4.136 eV
    80.    80 a        2.000        -0.171806 H =        -4.675 eV

    I found that the HOMO LUMO gap is too small, like a conical intersection.
    I think that there is a parameter set in turbomole, Egrad will stop when the HOMO LUMO gap is lower than the parameter.
    My question:  Is there any key word to change the parameter, so that egrad can run normally with such small HOMO LUMO gap?

     Thanks!

[Arnim]

Hi,

there is no parameter, that checks the HOMO-LUMO gap.

Cheers,
Arnim