The luminescence energy and intensity of d(10) copper(I), silver(I) and gold(I) dicyanide nanoclusters exhibit high tunability as energy transfer donors in different organic solvents. For Tb3+ acceptor ions, the energy transfer efficiency, which is proportional to the spectral overlap between the donor emission and the acceptor absorption, depends on the solvent tunability of the donor emission energy. For Eu3+ acceptor ions, energy transfer can be 'tuned off or 'tuned on' as the solvent dependent donor emission energy becomes in resonance with a charge transfer state or with the L-5(6) Eu3+ ion state, respectively. (C) 2007 Elsevier B.V. All rights reserved.