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## Additional Recommendations For Excited-state TreatmentsAmong the available schemes provided by CFOUR, the The corresponding excited-state calculations can be performed as - excited-state calculations are no
**black-box**calculations and a**careful checking**of the results (is the required state obtained in the calculation?) is warranted; - specification of the
**initial guess**via an %excite* section is preferred, as this allows a more**focussed**search on the excited state of interest, while when using the keyword**ESTATE_SYM**the corresponding initial guesses are generated in a CIS calculations; - using a
**computational**RHF reference allows just to compute**singlet excitation energies**,**triplet excitation energies**for closed-shell molecules require a**computational UHF**reference. In addition, the required triplet-excited states can be only obtained using a %excite* guess; - within
**analytic gradient calculations**for excited states, just**one excited state**can be treated at the time.
Concerning calculations using While CFOUR provides also Note also that the keyword |

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