First-principles study of the optical properties of pure α-Al2O3 and La aluminates S. M. Hosseini, H. A. Rahnamaye Aliabad and A. Kompany Eur. Phys. J. B, 43 4 (2005) 439-444 Published online: 30 March 2005 DOI: 10.1140/epjb/e2005-00076-8