LAUSR

Abstract We investigated structural, electronic and optical properties of quasi-one-dimensional barium zinc chalcogenides Ba 2 ZnS 3 , Ba 2 ZnSe 3 and Ba 2 ZnTe 3 using density functional theory as implemented in VASP. The structures crystallise in the orthorhombic space group D 2 h 16 − Pnma and were studied using PBE and HSE06 functionals incorporating Van der Waals corrections using DFT-D3 method. It was found that the calculated structures agree well with experimental structures. Electronic structure calculations with HSE06 show that these materials are wide band gap semiconductors with a direct gap at the centre of the Brilluoin zone, the Γ point. Optical properties reveal that the materials exhibit high optical anisotropy with large birefringence.