2. Homo and . Ru, 56% C8 and 8% Cu 3 for the HOMO-1) This suggests that there should be some communication between the ruthenium end-groups across the Cu(I) and Ag(I) clusters, and that the two oxidation waves observed in the CVs of

. Wilk-nusair-parametrisation, LDA) with gradient correction for exchange (Becke88) [74] and correlation (Perdew86) [75]. The numerical integration procedure applied for the calculations was that developed by teVelde et al. [76]. The atom electronic configurations [77] were described using the basis IV available in the ADF code, i.e., by a triple-? Slater-type orbital (STO) basis set for H 1s, C 2s and 2p and P 3s and 3p augmented with a 3d single-? polarisation function for C and P and with a 2p single-? polarisation function for H. A triple-? STO basis set was also used for Cu 3d and 4s, for Ru 4d and 5s, for Ag 4d and 5s, augmented with a single-? 4p polarization function for

C. Ru and A. , A frozen-core approximation was used to treat the core shells up to 1s for C, 2p for P, 3p for Cu, 4p for Ru, and 4p for Ag [72]. Geometries were optimized using the analytical gradient method implemented by Verluis

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M. Cu, Ag) have been obtained from HC 4 [ML n ] and [M 2 (dppm) 2 (NCMe) x ] 2+ (x = 3,4) and structurally characterised. Electrochemical and DFT studies have shown that the ML n groups interact