The structure and emission spectrum of the europium cryptate containing 3,3'-biisoquinoline-2,2'-dioxide(BiqO(2)), are investigated in the frame-work of the Sparkle/AM1 model and Judd-Ofelt theory. The simulated structure is compared to the X-ray measurements found in literature. The satisfactory similarity between them can be noted. The differences can be attributed to the fact that the simulation is performed in vacuum. The good predictions of the intensity parameters and the theoretical quantum yields calculated to Sparkle/AM1 and X-ray structures, indicate that the Sparkle/AM1 model can be successfully used for simulating the local environment of the EU3+, even involving large molecules as cryptates. (c) 2007 Elsevier B.V. All rights reserved.