Outer Valence Green Function

The He(l) photoelectron spectra <1997JMT(392)21> of ATQ and TATCD were measured and interpreted by means of ab initio outer valence Green function calculations (OVGF). These gave an overall consistent agreement with the main features in the spectra, in particular of the n (N) bands. 

Gleiter et al. measured the He(Ia) photoelectron (PE) spectra of the parent heterocycle and its five mono-, di-, and tri-methyl derivatives, and assigned the PE bands by comparison with the results of MO calculations <83CPL(97)94>. They showed that the spectral assignment was consistent with the results of four very different theoretical procedures (HMO, EWMO, HAM/3, and LOGO MB). Recently, it has been reported that the PE spectra were reproduced well by the Outer-Valence Green Function approach with PM3 <91JCS(P2)1865> (see Table 3). 

Second-order and third-order results often bracket the true correction to pF - Three schemes that scale the third-order terms in various ways are known as the Outer Valence Green s Function (OVGF) [8], In OVGF calculations, one of these three recipes is chosen as the recommended one according to rules based on numerical criteria. These criteria involve quantities that are derived from ratios of various constituent terms of the self-energy matrix elements. Average absolute errors for closed-shell molecules are somewhat larger than for P3 [31]. 

FOCI - first-order configuration interaction. Outer valence Green s function. Extended two-particle-hole Tamm-Dancoff approximation. 

Vertical ionization energies. Outer valence Green s function method. Koopmans Theorem values are also... 

OFGF outer valence Green s function (method)... 

Quasi-particle P3 calculations produce better accuracy than outer valence Green s function (OVGF). An application of the photoelectron spectrum of r-tetrazine illustrates the ability of the P3 method to predict correct final-stage orderings <1997IJQ291>. 

In Table 9, the IP values of aniline are compared with orbital ena-gies obtained by quantum chemical calculations. The agreement is sufficient for the assignments even for most of the higher IPs, although the sequence of 6a" and 12a is inverted by the semi-empirical methods relative to the ab initio results. The smallest deviations—at least for the lower IPs—is found for the outer valence Green s function (OVGF) technique, coupled with semi-empirical AMl calculations. 

We have used the outer valence Green s function (OVGF) method coupled with semiempirical approximations to calculate the IPs of a variety of molecules ranging from benzene to fullerenes. We also extended the method to calculate IPs... 

Similar accuracy (0.2-0.3 eV for valence ionization energies below 20 eV) is available using propagator methods in conjunction with triple-f basis sets. These propagator methods are known in the literature as the outer valence Green s function (OVGF) and partial-third order (P3)... 

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... 

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