PW91 Perdew-Wang

PW91 (Perdew, Wang 1991) a gradient corrected DFT method QCI (quadratic conhguration interaction) a correlated ah initio method QMC (quantum Monte Carlo) an explicitly correlated ah initio method QM/MM a technique in which orbital-based calculations and molecular mechanics calculations are combined into one calculation QSAR (quantitative structure-activity relationship) a technique for computing chemical properties, particularly as applied to biological activity QSPR (quantitative structure-property relationship) a technique for computing chemical properties... 

Reference TMS <513C(calc) = 183.5 ppm, geometry (Cl) B3LYP/6-31G(d) NMR calculation SOS DFT PW91 (Perdew-Wang 91) IGLO IB. 

PW91 Perdew-Wang 91 exchange-correlation functional... 

Table4.4 Spectroscopic properties for Au2 q= -1,0, + 1) using ab-initio (Hartree Fock, HF, second-order Moller-Plesset, MP2, and coupled cluster, CCSD(T)) and DFT (local spin-density approximation, LSDA, Perdew-Wang CCA, PW91, and Becke three-parameter Lee-Yang-Parr functional, B3LYP) methods at the RPPA level of theory.

TABLE 9.2 Perdew-Wang (PW91) Binding Energies of O and O2 on the Pt and Pt3Co Alloy Surfaces. Reprinted with Permission from Xu et al. [2004]... 

Unless otherwise stated, all of our calculations used the generalized gradient approximation as defined by the Perdew-Wang 91 functional. In shorthand, we used PW91-GGA calculations. Unless otherwise stated k points were placed in reciprocal space using the Monkhorst-Pack method. Some specific details for the calculations from each section of the chapter are listed below. 

Nonempirical GGA functionals satisfy the uniform density limit. In addition, they satisfy several known, exact properties of the exchange-correlation hole. Two widely used nonempirical functionals that satisfy these properties are the Perdew-Wang 91 (PW91) functional and the Perdew-Burke-Ernzerhof (PBE) functional. Because GGA functionals include more physical ingredients than the LDA functional, it is often assumed that nonempirical GGA functionals should be more accurate than the LDA. This is quite often true, but there are exceptions. One example is in the calculation of the surface energy of transition metals and oxides. 

PW91 Perdew and Wang s (sic) 1991 GGA correlation functional. Perdew, J. P. 1991. In Electronic Structure of Solids 91, Ziesche, P. and Eschig, H., Eds., Akademie Verlag Berlin, 11. 

For the DFT shift calculations, a combination of the Becke exchange [66] and the Perdew-Wang (PW91) correlation functionals [67] is used while the geometries needed for the shift calculations are normally determined by the so-called B3LYP method, which is based on Becke s three parameter functional (1) [68,69]... 

RPBE [17], PW91 (Perdew and Wang 1991) [18, 19] and BLYP (the exchange func-honal of Becke [20] with correlation functional from by Lee, Yang and Parr) [21], In the remainder of the text we shall use these acronyms without further referencing. 

Finally, the Perdew-Wang (PW91) exchange and correlation [42-44] functionals are the only ones in the GGA that are designed from purely first principles. 

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