Generation of abstract POFs

A conformer is a realization of an abstract POF if the abstract POF describes the orientations of that conformer. Note that a realization may not exist for an abstract POF even if the function fulfills all tested criteria of Step 1. We distinguish three kinds of abstract POFs  

It is crucial to provide a set of combinatorial tests on the combinatorial level to exclude as many non-realizable and chemically-non-realizable abstract POFs as possible. We distinguish two kinds of tests  

The cyclohexane example was presented in more detail in earlier articles (103, 104]. However, zero orientations were not considered in these. This led to 13 abstract POFs containing positive and negative orientations only, the three chemically realizable ones among them. Additional restrictions discussed in [103] are described in the following sections. For the example of cyclohexane, they reduce the number of abstract full orientation functions as reported there. However, the restrictions do not reduce the number of candidates when considering abstract POFs with respect to the given selection S. 

If we assume that there are no conformers with four adjacent atoms in one plane in saturated rings of size 6, we can use this as a criterion for chemical realizabiUty  

We restrict the number of 92 non-isomorphic abstract POFs to 13 abstract PDFs without any zero orientation. 

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