Green’s functions many-body

The photoelectron spectra of pyridazine have been interpreted on the basis of many-body Green s function calculations both for the outer and the inner valence region. The calculations confirm that ionization of the first n-electron occurs at lower energy than of the first TT-electron (79MI21201). A large number of bands in the photoelectron spectrum of 3,6-diphenylpyridazine in stretched polymer sheets have been assigned to transitions predicted... 

In the standard choice BHF the self-consistency requirement (5) is restricted to hole states (k < kF, the Fermi momentum) only, while the free spectrum is kept for particle states k > kF- The resulting gap in the s.p. spectrum at k = kF is avoided in the continuous-choice BHF (ccBHF), where Eq. (5) is used for both hole and particle states. The continuous choice for the s.p. spectrum is closer in spirit to many-body Green s function perturbation theory (see below). Moreover, recent results indicate [6, 7] that the contribution of higher-order terms in the hole-line expansion is considerably smaller if the continuous choice is used. 

The propagator technique, which attempts to solve the hierarchy of equations for the many-body Green s function, has been faciUtated by the use of inner projection techniques and the superoperator representation of Goscinski and Lukman. Ohrn and co-workers have applied these... 

The PE spectra of difluorodiacetylene (17a) and perfluoro-1,3-pentadiyne (19) have also been recorded. In the case of 17a as well as 7a the assignment is supported by a calculation using the many-body Green s function approach. ... 

THE ONfi-PARTtCLE MANY-BODY GREEN S FUNCTION 403... 

Mattuck, R. D., Guide to Feynman Diagrams in the Many-Body Problem, 2nd ed., McGraw-Hill, New York, 1976. An entertaining book which discusses many-body Green s functions from the time-dependent point of view. Its only disadvantage to chemists is that the emphasis is on treating infinite systems where the basis functions are plane waves. 

Chapter 7. The One-Partide Many-Body Green s Function 380... 

Chapter 7 contains a brief introduction to the use of the one-particle many-body Green s function in quantum chemistry. Our scope is restricted to discussing ionization potentials and electron affinities. The chapter is directed towards a reader having no knowledge of second quantization or Green s functions, even in a simple context. 

Interestingly, a conical intersection very similar to that of the S i(n7r ) and S 2(7T7r ) neutral excited states has been found for the n and n hole states of the pyrazine cation.A linear vibronic-coupling model has been constructed for the and states of the pyrazine cation employing many-body Green s function methods for the calculation of the vibronic-coupling parameters. The ah initio calculated photoelectron spectrum of the Ag n ) and states is compared in Fig. 7 with the... 

Onida G, Reining L, Rubio A (2002) Electronic excitations density-functional versus many-body Green s function approaches. Rev Mod Phys 74 601-659 Ossicini S (1997) Porous silicon modeled as idealized quantum wires. In Canham L (ed) Properties of porous silicon. INSPEC, London, p 207... 

Here indicates an infinitesimal positive time-shift of t, i.e. = lime o(t + e ). The KS and the full many-body Green s function are defined by the ground-state expectation values of the time-ordered product of the corresponding field operators, and... 

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