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Abstract
Aim: Calculation of dynamical electron
correlation energy within Hartree Fock formalism
to achieve post Hartree Fock accuracy.
Achievement: Using intermediate Hamiltonian
technique and perturbation methodology we can
construct a weave equation which on projection
gives very simple equation for correlation
energy. Correlation energy only depends on the
amount of perturbation. This method is applied
for few small molecules. It is found that this
method produces very accurate results which is
comparable to CCSD method.
Conclusion: The present method which is
termed as Extended Hartree Fock (EHF)
method is proved to be a very good tool for
electronic structure theory as its computational
requirement is equivalent to HF method but its
accuracy is comparable to Coupled Cluster
based methods.
correlation energy within Hartree Fock formalism
to achieve post Hartree Fock accuracy.
Achievement: Using intermediate Hamiltonian
technique and perturbation methodology we can
construct a weave equation which on projection
gives very simple equation for correlation
energy. Correlation energy only depends on the
amount of perturbation. This method is applied
for few small molecules. It is found that this
method produces very accurate results which is
comparable to CCSD method.
Conclusion: The present method which is
termed as Extended Hartree Fock (EHF)
method is proved to be a very good tool for
electronic structure theory as its computational
requirement is equivalent to HF method but its
accuracy is comparable to Coupled Cluster
based methods.
