The synthesis of Ru(CCC 6 H 4 -4-NO 2 )(κ 2 -dppf)(η 5 -C 5 H 5 ) (1) is reported, together with spectroscopic, X-ray structural, linear optical and quadratic nonlinear optical (NLO) studies of 1 and Ru(CCPh)(κ 2 -dppf)(η 5 -C 5 H 5 ) (2), the last-mentioned using the hyper-Rayleigh scattering technique at 1064 nm. Quadratic nonlinearities for these dppf-containing complexes are comparable to those of their dppe-containing analogues and significantly greater than carbonyl-containing analogues. The linear optical and quadratic NLO properties of 1, 2 and their dppe-containing analogues have been rationalized by time-dependent density functional theory calculations.