Some materials can display magnetic order despite having spin-singlet ground state on individual magnetic sites. This arises due to exchange interactions mixing excited crystal electric field states. Here, Gao et al study and example of such a system, Ni2Mo3O8, and find that crystal electric field states in both the paramagnetic and antiferromagnetic states exhibit dispersive excitations.
- Bin Gao
- Tong Chen
- Pengcheng Dai