Force fields future developments

In conclusion, asymmetric catalysis is emerging as an almost mature field, after a quarter of a century of active investigations. Asymmetric catalysis is the topic of many international meetings [124] and is periodically reviewed in many journals and books. The continuous interest of the academic and the industrial communities in enantioselective catalysis will be, without any doubt, a strong driving force for new developments in the near future. 

The existence of thermotropic liquid crystalline phases allows the manipulation of morphology and thus their optical properties by external forces," including magnetic fields. Such phases will play a role in future development of aligned layers for polarized emission and other LED-type applications. 

This outlook summarizes some new and expected future developments in investigating organometallic chemistry using force field-based techniques. 

At this point (early 1980s) it became clear that we really needed to divide the treatment of aromatic heterocycles into two different, general cases. The first case is ordinary heterocyclic molecules. For those, the calculations are carried out as previously described. The second case would be when we wished to carry out a calculation on a macromolecule such as DNA, which has a great many molecules of nucleic acid bases present, and we do not want to do a quantum mechanical calculation on each of them one by one. We wished to carry out the quantum mechanical calculation for a given base once, and then develop a force field that will reproduce the structure of each of these bases adequately. These molecular force fields are then stored in a library. For future calculations involving those molecules then, one obtains from the library the appropriate force field for each of those molecules as needed, and they are then used in the ordinary molecular mechanical manner. 

Force fields for different ILs based on pyridinium, tetraalkylpho-sphonium, tetraalkylammonium and guanidinium cations were also developed. More force fields for functional ILs were also suggested to study the corresponding functional properties, such as tetraalkylphosphonium-based IL with amino acids as anions. The future of force fields is in developing force fields for functional ILs and optimizing the force field parameters for ILs under complex conditions. 

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