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تسجيل مستخدم جديدOn The Inclusion of One Double Within CIS and TD-DFT
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We present an improved approach for generating a set of optimized frontier orbitals (HOMO and LUMO) that minimizes the energy of one double configuration. We further benchmark the effect of including such a double within a CIS or TD-DFT configuration interaction Hamiltonian for a set of test cases. We find that, although we cannot achieve quantitative accuracy, the algorithm is quite robust and routinely delivers an enormous qualitative improvement to standard single-reference electronic structure calculations.
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