EOM-CCSD for triplets excited states


I am strugling to obtain separated triplet energies from singlet in EOM-CCSD calculations. Attached I put my input for ethanol molecule. Is there any way to calculate singlet and triplet excited states separately? Or simply to identify the multiplicity of states in the output?
ethanol.txt (379 Bytes)

Kind regards.

When running a singlet ground state through the UHF-EOM-CCSD code (as you’re doing in your ethanol example), you should be able to identify the singlets vs. triplets based on the relative signs of the single-excitation coefficients corresponding to alpha and beta excitation pairs. For a given occupied–>virtual MO transition has the same sign on the alpha (RIA) and beta (Ria) coefficients, then it’s a singlet. If the signs are opposite, then it’s a triplet. (Note that the coefficients should have identical absolute values if the states are properly spin adapted.)

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Thank you crawdad, this solves my problem.

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