Crystal spacing predicts magnetic states in complex alloys better than electron count

In materials chemistry, identifying common parameters that can organize magnetic ground states across complex intermetallic compounds remains a central challenge. Researchers have long used chemically tunable parameters to control magnetic properties. One is valence-electron concentration, commonly discussed as the electron-per-atom (e/a) ratio. The e/a ratio has been widely used to classify magnetic ground states in metallic systems such as Heusler alloys and approximant crystals.