Organometallic complexes for nonlinear optics. 52. Syntheses, structural, spectroscopic, quadratic nonlinear optical, and theoretical studies of Ru(C2C6H4R-4)(κ2-dppf)(η5-C5H5) (R = H, NO2)

The synthesis of Ru(CCC6H4-4-NO2)(κ2-dppf)(η5-C5H5) (1) is reported, together with spectroscopic, X-ray structural, linear optical and quadratic nonlinear optical (NLO) studies of 1 and Ru(CCPh)(κ2-dppf)(η5-C5H5) (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.

Graphical abstractThe syntheses and X-ray structural studies of Ru(CCC6H4-4-X)(κ2-dppf)(η5-C5H5) (X = H, NO2) are reported; experimental linear optical properties and quadratic nonlinearities from hyper-Rayleigh scattering studies at 1064 nm are contrasted and rationalized by time-dependent density functional theory studies.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Nonlinearities for ruthenium alkynyl complexes are comparatively large with co-ligand dppf. ► Redox-active co-ligands such as dppf afford additional NLO redox-switching possibilities. ► TD-DFT studies reproduce trends in experimental linear and particularly nonlinear optical properties.