  Observations of the outflows of asymptotic giant branch (AGB) stars continue
to reveal their chemical and dynamical complexity. Spherical asymmetries, such
as spirals and disks, are prevalent and thought to be caused by binary
interaction with a (sub)stellar companion. Furthermore, high density outflows
show evidence of dust-gas interactions. The classical chemical model of these
outflows - a gas-phase only, spherically symmetric chemical kinetics model - is
hence not appropriate for a majority of observed outflows. We have included
several physical and chemical advancements step-by-step: a porous density
distribution, dust-gas chemistry, and internal UV photons originating from a
close-by stellar companion. Now, we combine these layers of complexity into the
most chemically and physically advanced chemical kinetics model of AGB outflows
to date. By varying over all model parameters, we obtain a holistic view of the
outflow's composition and how it (inter)depends on the different complexities.
A stellar companion has the largest influence, especially when combined with a
porous outflow. We compile sets of gas-phase molecules that trace the
importance of dust-gas chemistry and allow us to infer the presence of a
companion and porosity of the outflow. This shows that our new chemical model
can be used to infer physical and chemical properties of specific outflows, as
long as a suitable range of molecules is observed.
