Cookies

We use cookies to ensure that we give you the best experience on our website. You can change your cookie settings at any time. Otherwise, we'll assume you're OK to continue.

Durham University

Department of Chemistry

Publication details for Dr Lars-Olof Pålsson

Palsson, L.O., Vaughan, H.L., Smith, A., Szablewski, M., Cross, G.H., Roberts, T., Masutani, A., Yasuda, A., Beeby, A. & Bloor, D. (2006). Guest-host interactions between dichroic dyes and anisotropic hosts. Journal of luminescence 117(1): 113-122.

Author(s) from Durham

Abstract

The guest–host interaction between dichroic dyes and anistropic hosts has been investigated by means of optical spectroscopy. Two different TCNQ adducts; 2-{4-[(2,6-dimethylmorpholin-4-yl)(4-metylpiperidin-1-yl)methylene]cyclohexa-2,5-dien-1-ylidene} malononitrile (MORPIP) and 2-{4-[cyclohex-1-yltetrahydropyrimidin-2(1H-ylidene]cyclohexa-2,5-dien-1-ylidine} malononitrile (AMINO) have been examined dispersed in a range of nematic liquid crystal mixtures. The result is a substantial impact on the absorption and luminescence when compared to the situation in isotropic solvents. The excited state decay exhibits a complex behaviour showing a multi-exponential decay of the time-resolved luminescence. The photoluminescence quantum yields of the chromophores, also shows strong host dependence. For AMINO, we observe a trend which is indicative of a viscosity dependence. The observations are discussed in view of different solvent–solute interactions between guest and host.