Symmetric trans-[Pt(PPh3)2(CCR)2] and unsymmetrical trans-[Pt(PPh3)2Cl(CCR)], (R=C6H4-pNO2, C6H4-pOCH3), Pt(II) acetylides were prepared and characterised, as well as unsymmetrical Pt(II) bis-acetylides, trans-[Pt(PPh3)2(CCR)(CCR′)], (R=C6H4-pNO2, R′=C6H5; R=C6H4-pOCH3, R′=C6H5; R=C6H4-pOCH3, R′=C6H4-pNO2; R=C6H4-pNO2, R′=[(η5-C5H4)Fe(η5-C5H5)]). Also symmetric Pd(II) bis-acetylides, trans-[Pd(PPh3)2(CCR)2] (R=C6H4-pNO2, C6H5) were synthesised and characterised by IR, NMR, and UV-vis spectroscopies. The optical properties of the new complexes were compared within a series of known Pt(II) complexes containing different phosphines and cis-trans configuration. The absorption and photoluminescence spectra indicate that the emission is found in the range 355-600 nm, depending on the nature of the acetylide ligand bound to Pt. Measurements of SHG for the unsymmetrical bis-acetylides dispersed in polymethylmethacrylate (PMMA) show that the second-order nonlinear optical (NLO) properties depend on the strength of the donor-acceptor substituent of the acetylide ligand. Third-order NLO properties (in particular the nonlinear absorption coefficient α2) were measured by the Z-scan technique; strong push-push and pull-pull substituents on the Pt(II) symmetric bis-acetylides induce electronic delocalisation and tuning of the NLO properties. The single crystal X-ray structure of trans-[Pt(PPh3)2(CC-C6H5)(CC-C6H4NO2)] shows that the unsymmetrical molecule crystallised in the Pbca centric space groups. © 2001 Elsevier Science B.V.
All Science Journal Classification (ASJC) codes
- Physical and Theoretical Chemistry
- Organic Chemistry
- Inorganic Chemistry
- Materials Chemistry
D'Amato, R., Furlani, A., Colapietro, M., Portalone, G., Casalboni, M., Falconieri, M., & Russo, M. V. (2001). Synthesis, characterisation and optical properties of symmetrical and unsymmetrical Pt(II) and Pd(II) bis-acetylides. Crystal structure of trans-[Pt(PPh. Journal of Organometallic Chemistry, 627(1), 13 - 22. https://doi.org/10.1016/S0022-328X(00)00791-9