This dataset supports the paper "Modelling atomic and nanoscale structure in the silicon-oxygen system through active machine-learning". The paper is online here: The following files are provided: Potential files for the complex ACE potential for Si-O and additionally for the linear and Finnis-Sinclair ACE ("potential") Training database in a xyz file format as well as pckl.gzip with weights, which have been used for the fits. Includes also the parameter file for the DFT calculations ("database") Parameters files, which have been used for fitting the potentials ("fitting") Amorphous matrix embedding example script to extract the cells from the large-scale simulations as well as a script for the LAMMPS simulation to amorphize the boundaries ("amorphous_matrix_embedding") Results of various simulations with corresponding input scripts, input structures and analysis scripts ("results") High pressure simulations: Compression of amorphous silica up to 175 GPa, energy-volume curves, enthalpies Phase diagram: Input files for the calculation of the free energy and scripts to analyse the data to generate a phase diagram SiO: Contains the amorphous and partially crystalline structure files for the SiO models and the small-scale Si-SiO2 interface models. Moreover, files with structure factor data, crystallinity and interface area can be found here. Surfaces: Aerogel structures, which have been shown in the paper and the small-scale amorphous surface models with corresponding DFT data. It also includes the bulk reference data of the small-scale amorphous surface models, which is necessary to calculate the surface energy. Testsets: Include the testsets referenced in Table 1 and Supplementary Table 3. SiO2: Contains SiO2 structural models generated by the hybrid approach and using only the ACE potential.