The TCCC conformer of cyclodecane

A prospective user of a potential energy function Is first of all Interested In Its reliability. I hope to have shown by my examples In sections 9 1 and 9 2 and In this chapter that a parameter set may be good or just good enough for some purposes but Insufficient for others. This applies also to optimised sets and does not mean that a set Is not consistent. Rather, the model behind the potential energy function Is too primitive, or the parametrlsatlon behind the parameter set Is not well chosen for the purpose. 

A short summary of what we had obtained with un-optlmlsed potential 

The conclusion Is therefore that PEP302, PEP303 and PEP304 are more reliable for prediction than PEP401, and that good conformations and thermodynamic properties may be expected from the former, that conformations from PEP304 are best, at the expense of thermodynamic functions. 

The glory of young men is their strength, the dignity of old men their grey hair. 

Optimisation also on crystal structures is desirable, despite the considerably increased complexity of the programs, because crystal packing is determined exclusively by non-bonded interactions conversely, therefore, crystal packing is eminently suitable for optimisation of non-bonded energy function parameters. 

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