In the supporting information (SI), we provide a description of how to evaluate an MO on a real-space 3D grid. We also provide another way of quantifying helicality by fitting the equation for a helix to the highest isovalue along the carbon-chain. We use the spatial propagation of the nodal plane in the following because it is conceptually simpler and more robust in less well-defined helical systems. We slice the MO into xy-planes along the z-axis (the molecular axis of the carbon chain).