The preferential Li+ solvation in aqueous ammonia has been revisited by performing an extended ab initio QM/MM MD simulation, in which the QM region's size was enlarged to 4.2 angstrom radius. The use of larger QM region leads to a clear water preference with an arrangement of Li+[(H2O)(4)][(H2O)(4)] type, compared to the preferred Li+[(H2O)(3)NH3][(H2O)(4)(NH3)(2)] structure obtained by a previous QM/MM simulation using a small QM region not comprising the second solvation shell. The observed discrepancies clearly demonstrate the importance of quantum chemical treatment of the second shell in order to obtain a reliable and accurate description of this solvated ion. (C) 2008 Elsevier B.V. All rights reserved.