Error computing triplets in TDDFT

PSI4 version: 1.4rc1

I am attempting to generate singlet and triplet excitations with TD-DFT. The following minimal input gives me an error:

molecule {
    N   1   1
set {
    reference RHF
    TDSCF_States [10]
    TDSCF_Triplets also

TDSCF: Restricted Vx kernel only spin-adapted for singlets

When I attempt to use a UHF reference, I get the following error:

TDSCF: Cannot compute triplets with an unrestricted reference

The only way I can get it to run is if I switch from DFT to SCF. Is there a way to perform triplet excitations with TD-DFT in PSI4, or do I need to add additional keyword(s)?

Please read the manual. These are known limitations. You’re welcome to file a GitHub issue, since I don’t think there is one yet.

As for how hard these would be to add, I’ll leave promising DFT features to somebody else. I have DCT features to deal with.

Thanks, I had assumed that if I used a UHF reference I might be able to force it to work, but apparently not.

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