Symmetry conserving coupled cluster doubles wave function and the self-consistent odd particle number RPA
نویسندگان
چکیده
منابع مشابه
Pair extended coupled cluster doubles.
The accurate and efficient description of strongly correlated systems remains an important challenge for computational methods. Doubly occupied configuration interaction (DOCI), in which all electrons are paired and no correlations which break these pairs are permitted, can in many cases provide an accurate account of strong correlations, albeit at combinatorial computational cost. Recently, th...
متن کاملSelf-consistent Green’s function and RPA studies of nuclei
where E PT is the contribution to the total binding energy in second order perturbation theory. A perturbative expansion of the RPA equations shows that (i) the sum in Eq. (1) must also include charge exchange modes and (ii) E PT is double counted and must be subtracted [3]. This leads to an improved description of the binding energies of most closed shell nuclei, up to Pb, as shown in Fig. 1 [...
متن کاملConserving Approximations vs. Two-Particle Self-Consistent Approach
The conserving approximation scheme to many-body problems was developed by Kadanoff and Baym using the functional-derivative approach. Another approach for the Hubbard model also satisfies conservation laws, but in addition it satisfies the Pauli principle and a number of sum rules. A concise formal derivation of that approach, using functional derivatives, is given in this conference paper to ...
متن کاملSize-consistent wave functions for nondynamical correlation energy: The valence active space optimized orbital coupled-cluster doubles model
The nondynamical correlation energy may be defined as the difference between full configuration interaction within the space of all valence orbitals and a single determinant of molecular orbitals ~Hartree–Fock theory!. In order to describe bond breaking, diradicals, and other electronic structure problems where Hartree–Fock theory fails, a reliable description of nondynamical correlation is ess...
متن کاملEquivalence of particle-particle random phase approximation correlation energy and ladder-coupled-cluster doubles.
The recent proposal to determine the (exact) correlation energy based on pairing matrix fluctuations by van Aggelen et al. ["Exchange-correlation energy from pairing matrix fluctuation and the particle-particle random phase approximation," preprint arXiv:1306.4957 (2013)] revived the interest in the simplest approximation along this path: the particle-particle random phase approximation (pp-RPA...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The European Physical Journal A
سال: 2020
ISSN: 1434-6001,1434-601X
DOI: 10.1140/epja/s10050-020-00276-9