Spin-lattice-charge coupling in quasi-one-dimensional spin-chain NiTe2O5

A high-quality ${\mathrm{NiTe}}_{2}{\mathrm{O}}_{5}$ 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 $({T}_{\mathrm{N}})$ at 28.5 K. An apparent domelike dielectric anomaly near ${T}_{\mathrm{N}}$, with scaling of magnetodielectric (MD) coupling with magnetization $(\mathrm{MD}%\ensuremath{\propto}{M}^{2})$, 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 ${T}_{\mathrm{N}}$ originates through $p\text{\ensuremath{-}}d$ hybridization. Thus, the $p\text{\ensuremath{-}}d$ hybridization-induced magnetoelastic coupling is considered a possible mechanism for the higher-order ME effect in this quasi-one-dimensional spin-chain ${\mathrm{NiTe}}_{2}{\mathrm{O}}_{5}$.