  Hot Jupiters provide valuable natural laboratories for studying potential
contributions of high-energy radiation to prebiotic synthesis in the
atmospheres of exoplanets. In this fourth paper of the MOVES (Multiwavelength
Observations of an eVaporating Exoplanet and its Star) programme, we study the
effect of different types of high-energy radiation on the production of organic
and prebiotic molecules in the atmosphere of the hot Jupiter HD 189733b. Our
model combines X-ray and UV observations from the MOVES programme and 3D
climate simulations from the 3D Met Office Unified Model to simulate the
atmospheric composition and kinetic chemistry with the STAND2019 network. Also,
the effects of galactic cosmic rays and stellar energetic particles are
included. We find that the differences in the radiation field between the
irradiated dayside and the shadowed nightside lead to stronger changes in the
chemical abundances than the variability of the host star's XUV emission. We
identify ammonium (NH4+) and oxonium (H3O+) as fingerprint ions for the
ionization of the atmosphere by both galactic cosmic rays and stellar
particles. All considered types of high-energy radiation have an enhancing
effect on the abundance of key organic molecules such as hydrogen cyanide
(HCN), formaldehyde (CH2O), and ethylene (C2H4). The latter two are
intermediates in the production pathway of the amino acid glycine (C2H5NO2) and
abundant enough to be potentially detectable by JWST.
