Contributions from the Krylov group for a new Q-Chem release
نویسنده
چکیده
Q-Chem features the most complete set of EOM-CCSD models that enables accurate, robust, and efficient calculations of electronically excited states (EOM-EE-CCSD); ground and excited states of diradicals and triradicals (EOM-SF-CCSD, available only in Q-Chem); ionization potentials and electron attachment energies as well as problematic doublet radicals, cationor anionradicals, (EOM-IP/EA-CCSD). Conceptually, EOM is very similar to configuration interaction (CI): target EOM states are found by diagonalizing the so-called similarity transformed Hamiltonian H̄ = e−THeT :
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