D-MAE quantifies the mean absolute error between the pairwise distance matrices of the reference and predicted geometries. For a molecular structure 𝑹 with 𝑛 atoms, where the Cartesian coordinates of atom 𝑖 are (𝑥 " , 𝑦 " , 𝑧 " ), the pairwise Euclidean distance 𝐷 "# between two atoms 𝑖 and 𝑗 is given by: