Files: Model_I_Al2O3.xyz : The atomic structure of the bulk amorphous alumina model labelled as "model I" in Phys. Rev. Mater. 7, 045604 (2023). The model was originally generated in Colleoni et al. Appl. Phys. Lett. 107, 211601 (2015) via Born-Oppenheimer molecular dynamics simulations following a quench-from-the-melt approach. Atomic positions were further refined through a first-principle relaxation (DFT-PBE) in Phys. Rev. Mater. 7, 045604 (2023). This model contains 160 atoms, with the lattice parameters of: 11.47489566, 11.243676512, 12.778443806 angstrom, in the x, y and z direction, respectively. Model_II_Al2O3.xyz : The atomic structure of the bulk amorphous alumina model labelled as "model II" in Phys. Rev. Mater. 7, 045604 (2023). The model was originally generated (model G) in Momida et al Phys. Rev. B 73, 054108 (2006) by means of classical molecular dynamics through a quench-from-the-melt procedure. Atomic positions were further refined through a first-principle relaxation (DFT-PBE) in Phys. Rev. Mater. 7, 045604 (2023). This model contains 120 atoms, with the lattice parameters of: 7.738263, 12.34417, 12.98885 angstrom in the x, y and z direction, respectively. Model_III_Al2O3.xyz : The atomic structure of the bulk amorphous alumina model labelled as "model III" in Phys. Rev. Mater. 7, 045604 (2023). The model was originally generated (model H) in Momida et al Phys. Rev. B 73, 054108 (2006) by means of classical molecular dynamics through a quench-from-the-melt procedure. Atomic positions were further refined through a first-principle relaxation (DFT-PBE) in Phys. Rev. Mater. 7, 045604 (2023). This model contains 120 atoms, with the lattice parameters of: 7.539782995, 11.720314599, 14.267155669 angstrom in the x, y and z direction, respectively.