We present the synthesis and a detail investigation of structural and magnetic properties of polycrystalline [VO(HCOO)2⋅(H2O)] by means of x-ray diffraction, magnetic susceptibility, high-field magnetization, heat capacity, and electron spin resonance measurements. It crystallizes in a orthorhombic structure with space group Pcca. It features distorted VO6 octahedra connected via HCOO linker (formate anions) forming a two-dimensional square lattice network with a bilayered structure. Analysis of magnetic susceptibility, high field magnetization, and heat capacity data in terms of the frustrated square lattice model unambiguously establish quasi-two-dimensional nature of the compound with nearest neighbour interaction J1/kB≃11.7~K and next-nearest-neighbour interaction J2/kB≃0.02~K. It undergoes a N\'eel antiferromagnetic ordering at TN≃1.1~K. The ratio θCW/TN≃10.9 reflects excellent two-dimensionality of the spin-lattice in the compound. A strong in-plane anisotropy is inferred from the linear increase of TN with magnetic field, consistent with the structural data.
@article{arxiv.1908.06032,
title = {A case study of bilayered spin-$1/2$ square lattice compound [VO(HCOO)$_2\cdot$(H$_2$O)]},
author = {S. Guchhait and U. Arjun and P. K. Anjana and M. Sahoo and A. Thirumurugan and A. Madhi and Y. Skourski and B. Koo and J. Sichelschmidt and B. Schmidt and M. Baenitz and R. Nath},
journal= {arXiv preprint arXiv:1908.06032},
year = {2019}
}