A density functional (PBE, PBEsol, HSE06) study of the structural, electronic and optical properties of the ternary compounds AgAlX2 (X = S, Se, Te)G.M. Dongho Nguimdo and Daniel P. JoubertEur. Phys. J. B, 88 5 (2015) 113DOI: https://doi.org/10.1140/epjb/e2015-50478-x