The modelling framework we use has been applied in first principles studies on predicting the morphology of copper deposited on various doped TaN substrates. All density functional theory (DFT) calculations were performed using the Vienna Ab initio Simulation Package (VASP) software, version 5.4. The Perdew-Burke-Ernzerhof (PBE) generalized gradient approximation (GGA) approximation to the exchange-correlation functional was used. A plane-wave basis set was used for valence electrons and projector-augmented-wave (PAW) potentials were used for the core electrons. The valence electron configurations are 5d 3 6s 2 for Ta, 2s 2 2p 3 for N, 3d 10 4s 1 for Cu, 3d 8 4s 1 for Co and 4d 7 5s 1 for Ru. All calculations are spin polarised with no restrictions on the spin. Gaussian smearing with a width of 0.1 eV was used to treat partial occupancies.