Quadratic canonical transformation theory and higher order density matrices
نویسندگان
چکیده
منابع مشابه
Quadratic canonical transformation theory and higher order density matrices.
Canonical transformation (CT) theory provides a rigorously size-extensive description of dynamic correlation in multireference systems, with an accuracy superior to and cost scaling lower than complete active space second order perturbation theory. Here we expand our previous theory by investigating (i) a commutator approximation that is applied at quadratic, as opposed to linear, order in the ...
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ژورنال
عنوان ژورنال: The Journal of Chemical Physics
سال: 2009
ISSN: 0021-9606,1089-7690
DOI: 10.1063/1.3086932