Hybrid functionals B3LYP

As will be outlined later, even the use of the much more accurate, but still semiempirical hybrid functional B3LYP (15) carries on some of the DFT-inherent problems. 

In this study of the 3d metal oxides (ScO - ZnO) the popular hybrid functional B3LYP was used. The Gaussian 94 [20] and Gaussian 98 [21] programs were used. In these, the B3LYP exchange-correlation functional is of the form [22] ... 

For various hydrogen-bonded complexes, it was shown that common GGA functionals such as BLYP, BPW86, PW86P86 perform better than LDA.108 m, 113-117 -pjjg hybrid functional B3LYP perform as good or better then the GGA... 

Density functional theory calculations using the hybrid functional B3LYP have been performed to study tetrazole formation by intramolecular [2+3] dipolar cycloaddition of organic azides and nitriles <03JOC9076>. 

We have in the present chapter shown results from theoretical model system studies of the catalytic reaction mechanisms of three radical enzymes Galatose oxidase. Pyruvate formate-lyase and Ribonucleotide reductase. It is concluded that small models of the key parts of the active sites in combination with the DPT hybrid functional B3LYP and large basis sets provides a good description of the catalytic machineries, with low barriers for the rate determining steps and moderate overall exothermicity. The models employed are furthermore able to reproduce all the observed features in terms of spin distributions and reactive intermediates. 

Perhaps the most popular has been the hybride functional B3LYP [78] by Becke in which 20% of YP is replaced by AFS. We present in Table 3 a number of metal-ligand distances optimized by B3LYP [88]. For most systems, the error is only 0.02 A. In Table 4, we compare metal-ligand bond energies calculated by BLYP [76, 81] and B3LYP [76, 80]. Obviously, B3LYP represents a clear improvement over BLYP. 

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