A 16-electron dicationic dihydrogen complex [Ru(eta(2)-H center dot center dot center dot H)(PP)(2)][ OTf](2) [ 4; PP = (C6H5CH2)(2)PCH2CH2P(CH2C6H5)(2)] has been prepared and characterized by protonating the precursor hydride complex [Ru(H)(PP)(2))][OTf] (2) using HOTf. The hydride and dihydrogen complexes are stabilized via agostic interaction of the ortho C-H fragment of the phenyl ring on the benzyl group. The intact nature of the H - H bond in this derivative was established from the short spin - lattice relaxation time and the observation of a substantial J(H,D) of 22.0 Hz for the HD isotopomer. The H - H bond distance calculated from J( H, D) is 1.05 A, which falls under the category of elongated dihydrogen ligands.