Chemical representations for mixtures and formulations

While most of the mixtures and formulations of chemical compounds are directly handled by relational database systems the molfile format offers a notation for chemical structures that allows you to keep the consistency for structure searches and between structure databases and the alpha-numeric table that handles most of the information.
Technical Xylene, for example, is normally not split up between ortho-, meta-, or para-Xylene. The mixture can be drawn as

 
Sgroup data may be added to handle information about the composition of the mixture.

In this context formulations are defined as ordered mixtures. The following example is developed from a shampoo formulation and uses multiple Sgroups and PEG as described above in this article:

 
In the formulation above the substances Magnesium laurylsulfate, Ocamidopropyl betaine, Polysorbate 20, PEG 600, Citric acid and water are added stepwise, where c1, c2, … describes the order of the components within the formulation. The blue numbers and texts describe the composition of each component while the numbers in black represent the molecular weight of the component. For more information for the component c3 see “statistically distributed structural collections”.