Highly Entangled Magnetodielectric and Magnetostriction effects, and Spin-Phonon coupling in the Antiferromagnetic Ni${}_2$ScSbO${}_6$

Magnetic systems with noncentrosymmetric crystal structures are renowned for their complex magnetic ordering and diverse and fascinating physical properties. In this report, we provide a comprehensive study of the chiral magnetic system Ni${}_2$ScSbO${}_6$, which exhibits a robust incommensurate long-range antiferromagnetic spin ordering at a temperature of $T_N=62$~K, as revealed by bulk magnetization, specific heat, and neutron diffraction studies. This magnetic ordering triggers a series of intriguing phenomena, including prominent magnetodielectric coupling manifested by a dielectric peak at $T_N$, significant spin-phonon coupling resulting in strong phonon renormalization characterized by anomalous softening of various Raman modes, and a remarkable volume magnetostriction effect probed by high-resolution synchrotron X-ray diffraction. These phenomena are intricately interlinked, positioning the present system as a rare and interesting material.