The inset in Figure shows the 4 torsions considered in sulfadiazine. Using the same approach outlined above for alanine dipeptide, sulfadiazine's conformational FES was studied by analyzing the configurations sampled within a 1 µs single-molecule WTmetaD simulation. The resulting per-point FES cannot be fully visualized without dimensionality reduction, so the relative free energies and coordinates of each minimum are presented in Tab. I. Figure shows a 2D projection of the 4D perpoint FES created using SketchMap. This representation preserves the short-distance connectivity between data points, allowing the visualization of distinct free energy basins and the transition states between them, though the two axes of the new 2D projection are not physically meaningful themselves. It should be emphasized that the estimation of densities and the determination of the number and coordinates of the free energy minima are determined in the full 4-dimensional conformation space and that the projection in Figure serves only to assist in the visualization of the relationships between different conformers. It is possible to combine the 4dimensional information presented in Table with the 2-dimensional intuition provided by Figure . For example, the FES in Figure appears to be bisected by a diagonal channel, and indeed, by inspecting the torsion values of the conformer pairs 17 and 2, 10 and 6, 21 and 15, and 7 and 8, it can be determined that these conformers pairs are identical, and differ from each other in a symmetric rotation of π radians of γ 3 . This example serves to show how these 2D projections may be manually interpreted and to demonstrate how symmetry elements in the molecule's conformation space can be preserved in the 2D projection.