Spin-lattice-charge coupling in quasi-one-dimensional spin-chain NiTe2 O5

A high-quality NiTe2O5 single crystal was grown via the flux method and characterized using synchrotron x-ray diffraction (XRD) and electron probe microscopy techniques. The dc magnetization (M) confirms the antiferromagnetic long-range ordering temperature (TN) at 28.5 K. An apparent domelike dielectric anomaly near TN, with scaling of magnetodielectric (MD) coupling with magnetization (MD% ∝ M2), signifies higher-order magnetoelectric (ME) coupling. The critical finding is that magnetoelastic coupling plays a pivotal role in bridging the electrical and magnetic dipoles, which was further confirmed by temperature-dependent XRD. In addition, the theoretical charge density difference maps indicate that the emergence of electrical dipoles between the Ni and O atoms below TN originates through p-d hybridization. Thus, the p-d hybridization-induced magnetoelastic coupling is considered a possible mechanism for the higher-order ME effect in this quasi-one-dimensional spin-chain NiTe2O5.