Density functional theory calculations on monoclinic Lu2WO6 is carried out using the Cambridge Sequential Total Energy Package code. The result indicates that Lu2WO6 is a broad band gap semiconductor with an indirect band gap of 3.13 eV. Eu ions are trivalency and the average coordination number is 7.6(5), indicating that the site of Lu is occupied by Eu. The activation energy Delta E is calculated as 0314 eV. In addiation, the thermal quenching mechnism of Eu-activated Lu2WO6 and the different concentration quenching mechanisms for D-5(0) and D-5(1) emissions of Eu ions have been proposed. (C) 2015 Elsevier Ltd. All rights reserved.