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Valence universal cluster operator

Mukherjee et. alZ68-69/ formulated an explicitly connected CC theory for complete model space by invoking a valence universal cluster operator Q of the form... [Pg.335]

On the one hand, we can strive for a single cluster operator T, defining the valence universal wave operator U, U = exp(T), which will transform all the model space states ]< > ) into some linear combinations of the exact states jfl i), f = 1,2, , M, which in turn span the target space M, i.e.. [Pg.17]

Clearly, with this choice, not only are the equations for the core cluster amplitudes decoupled from the rest, but also the equations for the T1n cluster— amplitudes have only T m>amplitudes with mvalence values. It should again be noted that O acting on a P for m this approach uses implicitly a valence-universal wave-operator. [Pg.340]

Mukherjee/69/, use of the sufficiency conditions (7.3.9) amounts in effect to assuming that ft is a valence-universal wave-operator. In fact Haque has explicitly demonstrated/123/ that the use of a valence-universal ft in the Fock-space Bloch equation leads automatically to eqn (7.3.9) with the ad-hoc sufficiency requirement. We give the sketch of a general proof here, since it shows that the extra information content of a Fock-space ft, as opposed to a Hilbert space, can be used to advantage for ensuring the connectivity of the cluster amplitudes of S/93/. For a valence-universal ft, the Fock-space Bloch equation (6.1.15) leads to... [Pg.347]

In what follows, it will be useful to classify the parent n-valence IMS belonging to the space P, the complementary"active space, whose union with P forms the CMS, as R and the true virtual space containing inactive labels as Q. The cluster operators inducing the transition P+R are all labelled by valence lines, and will henceforth be denoted as quasi-open. The operators making transitions P- Q will be called open. The operators connecting model spaces only will be called closed. In general, for a valence-universal O, it so happens that products of quasi-open... [Pg.354]


See other pages where Valence universal cluster operator is mentioned: [Pg.136]    [Pg.149]    [Pg.136]    [Pg.149]    [Pg.333]    [Pg.76]    [Pg.18]    [Pg.309]    [Pg.299]    [Pg.165]    [Pg.583]    [Pg.242]    [Pg.24]   
See also in sourсe #XX -- [ Pg.17 ]

See also in sourсe #XX -- [ Pg.335 ]




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