B3LYP density functional methods

The keyword for a given density-functional method is formed by concatenating the symbols for its exchange and correlation functionals. For example, combining the Becke three-term (B3) exchange functional with the Lee-Yang-Parr (LYP) correlation functional leads to the popular B3LYP density functional method. 

A complementary paper was reported soon after by Adam, Bach and coworkers where eight transition structures for the epoxidation of the chiral allylic alcohol (Z)-3-methyl-3-penten-2-ol with peroxyformic acid were computed by the B3LYP density functional method with 6-31G(d) and 6-31G(d,p) basis sets. The four lowest-energy transition structures and their respective prereaction clusters were fuUy re-optimized by employing 6-31H-G(d,p) and correlation-consistent polarized valence triple- cc-pZTV basis sets. 

To study CO2 on clean Pd(lll), two different clusters Pdio(7,3) and Pd 15(10,5) were selected to represent mono-coordinated and bi-coordinated adsorption modes respectively. The local/outer separation described above was employed, pseudopotentials and basis sets chosen according to this partition. The hybrid B3LYP density functional method was used to explore the potential energy surface. The different optimizations converged to three unique species corresponding to two coordination models only. For theri -C coordination two different species were found, one being a physisorbed and... 

In their study on solvent effects on the properties of oligothiophenes, Fig. 9, Meng et calculated also the dipole moment for chains consisting of 2-6 thiophene units, either in the gas phase or in either w-hexane or water. The calculations were carried through using the B3LYP density-functional method for the solute and the polarizable continuum method for the solvent. As Table 30 shows, the solvent leads to an increase of the dipole moment, but in all cases a clear even-odd oscillatory pattern is identified. The latter can be related to the zigzag-like structure of the systems, cf. Fig. 9. 

In an earlier work, the same group had used Hartree-Fock calculations in calculating An for the most stable isomer of some chiral organic molecules in vacuum.In the more recent work, ° they extended the study in several directions. At first, they applied the B3LYP density-functional method, whereby also correlation effects were included. Second, they compared gas-phase results with those obtained for a solution, whereby they applied the polarizable-continuum method for the treatment of the solvent. And third, for some of the larger molecules they included the effects of having a mixture of more different stable structures in an approach very similar to that we discussed above in section III I for the calculation of the optical rotation. 

Table 44 The magnetochiral birefringence, An [in 10 cm /(T g)], per unit magnetic field and density for various chiral molecules. The theoretical method is either the Hartree-Fock or the B3LYP density-functional method, and the calculations were performed for either the gas phase or a solution. For the last two molecules, not only the most stable isomer was considered but also mixtures of six stable structures with populations according to a Boltzmann distribution. [a] is the specific optical rotation [in deg/(cm dm g)]. All results are from ref. 101... 

The bonding and charge distribution in the complexes of benzene with [Re(Tp)(CO)(L)] (L = NH3, Him, py, phosphine, CO, MeNC) have been calculated by LSDA and B3LYP density functional methods.195... 

Flarmonic and anharmonic frequencies of r-tetrazine have been compared using the B3LYP density functional method and medium-size basis sets <2004PCA4146> and DFT with the B97-1 exchange-correlation functional and a triple-C plus double polarization (TZ2P) basis set <1996JPC6973, 2004PCA3085>. 

COSY, NOESY and HETCOR NMR spectroscopies. The H and NMR chemical shifts of 3-PPA (C9H13N) were calculated by means of the Hartree-Fock (EIF), Becke-Lee-Yang-Parr (BLYP) and Becke-3-Lee-Yang-Parr (B3LYP) density functional methods with 6-311 -I- -I- G(d, p) basis set, respectively. The Fl, proton coupled and uncoupled N, DEPT, COSY, HETCOR, INADEQUATE NMR spectroscopies for 1,7-diamino-heptane and its magnitude of one bond coupling constants of... 

The mechanism of the CpTi-catalyzed styrene polymerization reaction was studied theoretically using the B3LYP density functional method. Three cases of the polymerization were examined, that is, Cp Ii(CH3)(CH(C6H5)CH3), CpTi(CH3)(CH(C6H5)CH3), and Cpri(CH(C6H5)CH3)+... 

A theoretical study has been carried out by Morokuma for the mechanism of Pt(0)-catalyzed alkyne and alkene diboration reactions with the B3LYP density functional method. The complexation energy between (0H)2B-B(0H)2 and Pt(PH3)2 has been calculated to be 3.7 kcal/mol, where the B-B and P-Pt-P axes are perpendicular to each other. The next step is the activation of the B—B bond, and the activation barrier has been calculated to be 12.5 kcal/mol, relative to the molecular complex (OH)2B— B(OH)2-Pt(PH3)2 or 8.8 kcal/mol relative to the reactants.In parallel, Sakaki theoretically investigated the insertion of Pt(PH3)2 into X2B—BX2 (X = H or OH) with the ab initio MO/MP4SDQ, SD-CI, and coupled cluster with double substitution methods. They found that this reaction proceeds with a moderate of 15 kcal/mol and a considerable of 20 kcal/mol for (OH)2B—B(OH)2. They noted that the B—B bond undergoes the insertion reaction of Pt(PH3)2 much more easily than does the C—C bond. Nowadays, the Pt-catalyzed diboration of terminal... 

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