Unconventional magnetic phase separation in γ-CoV₂O₆

We have explored the magnetism in the non-geometrically frustrated spin-chain system γ-CoV2O6 which possesses a complex magnetic exchange network. Our neutron diffraction patterns at low temperatures (T ≤ T_N = 6.6 K) are best described by a model in which two magnetic phases coexist in a volume ratio 65(1) : 35(1), with each phase consisting of a single spin modulation. This model fits previous studies and our observations better than the model proposed by Lenertz et al in J. Phys. Chem. C 118, 13981 (2014), which consisted of one phase with two spin modulations. By decreasing the temperature from T_N, the minority phase of our model undergoes an incommensurate-commensurate lock-in transition at T ^∗ = 5.6 K. Based on these results, we propose that phase separation is an alternative approach for degeneracy-lifting in frustrated magnets.