Fig. 3. Beyond-Heisenberg interactions in B20 germanides.
Angular dependence of the total energy without spin-orbit coupling for coplanar () and non-coplanar () antiferromagnetic spin configurations in a FeGe and b MnGe. Circles denote the first-principles results whereas blue and red solid lines indicate the fitted 4th-order exchange and chiral-chiral (CCI) contributions, respectively. Note the difference of scales between a and b.