Abstract
The molecular oxygen quenching of the solid-state emission from pure crystals of Delta-Ru(phen)(3)(PF(6))(2), Lambda-Ru(phen)(3)(PF(6))(2), and racemic Ru(phen)(3)(PF(6))(2) (phen = 1,10-phenanthroline) was studied by emission spectroscopy. Crystals of the pure enantiomers exhibit significant and nearly identical emission-intensity quenching [0.36(2) and 0.33(2), respectively] in the presence of air [where the fraction quenched is (I(nitrogen) - I(air))/I(nitrogen)]; in comparison, the racemic compound shows a much lower value [0.05(2)]. The large difference in the quenching behavior is a result of major structural differences between the two chiral salts and the racemic salt. The chiral compounds crystallize in the space groups P4(1) and P4(3), respectively, with toluene and acetonitrile molecules in the lattice that can be partially removed to create void-space channels. These open channels allow the diffusion of oxygen molecules within the crystals and enable efficient emission quenching that is not possible in the closely packed racemic salt. Lifetime measurements, thermal gravimetric analysis, and single-crystal X-ray structure determinations support these conclusions.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
