provide inferior results as compared to a fully equivariant model. As noted earlier, some conventions are ill-defined and discontinuous for certain values. Additionally, all tensor conventions based on the Cartesian tensor have an issue of explicitly defined axes which can cause confusion when parameters are predicted outside their range, which result in a change of the order of the eigenvalues. A full discussion of the numerical issues that arise when fitting with the tensor conventions can be found in the supplemental information.