Structure determination and characterization of two rare-earth molybdenum borate compounds: LnMoBO6 (Ln = La, Ce)

Abstract

The structural, optical, and electronic properties of two rare-earth molybdenum borate compounds, LnMoBO₆ (Ln = La, Ce), have been investigated by means of single-crystal X-ray diffraction, elemental analyses, and spectral measurements, as well as calculations of energy band structures, density of states, and optical response functions by the density functional method. The title compounds, which crystallize in monoclinic space groupP2₁/c, possess a similar network of interconnected [Ce₂(MoO₄)₂]²⁺ chains and [BO₂]⁻ wavy chains. Novel 1D molybdenum oxide chains are contained in their three-dimensional (3D) networks. The calculated results of crystal energy band structure by the density functional theory (DFT) method show that the solid-state compound LaMoBO₆ is a semiconductor with indirect band gaps.