Field-fitting

The method used to align molecules is still an area of contention. Applications like MOE-FlexAlign (30,39) and FlexS (37) are used to help discover different alignment configurations or to ensure that user bias has not entered the alignment scheme. Methods like MOE-FlexAlign and CoMFA s Field Fit (4) are useful if one knows the bioactive conformation or if the molecules of inter-... 

The photo-Fenton method of wastewater treatment is developed in two main fields fitting of the usable radiation range to the solar light and immobilization of the photo-Fenton catalyst. 

Progress has also been made in the simulation of the structures of 4-coordinate SiOj polymorphs both by using force fields fitted to experiment or to ah initio calculations, and by modified electron-gas calculations including the effect of oxygen polarization. Catlow et al. (1985) and Sanders et al. (1984) have established that O-Si-0 angle-dependent terms in the energy are needed to give proper structures and compressibilities... 

The structure proposed for benzene on nickel is shown in Fig. 7.21 [86]. The force field which successfully simulated the INS spectrum of [Cr(CO)3(ri -C6H6)] [89] was adapted for the calculation of the INS spectrum of benzene-Ni. The spectrum calculated for the structure of Fig. 7.21 was in excellent agreement with the observed spectrum of benzene on nickel. Force constants are listed in Table 7.14. We include also the results for benzene on platinum [87]. The distance of the centre of the benzene molecule was calculated in the force field fitting... 

The molecular alignment, i.e. the selection and relative orientation of a certain 3D structure out of several eonformers of each molecule, is the most important determinant in a CoMFA study. Recently, a field fit procedure [1(X)5, 1006] has been proposed to improve the alignment the objective of the field fit is to minimize the residual mean square differences between a fixed template field (consisting of... 

Force Fields Fit to High-Quality Quantum Mechanical Data... 

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