Photophysical properties of dendritic molecules

Luminescence is defined as emission of light by materials in the visible, UV, and IR spectral range after input of energy [2], Emission of light quanta by molecules from a (photo) excited state proceeds via transition of an electron to a lower energy level. Depending upon the way in which the excited state is generated, a distinction is made between photoluminescence, chemoluminescence, radioluminescence, and thermoluminescence (Table 5.1). In the case of photo- 

Dendrimer Chemistry. Fritz Vogtle, Gabriele Richardt and Nicole Werner Copyright 2009 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim ISBN 978-3-527-32066-0 

Fluorescence The electron returns from the excited state (lifetime ca. 10-9 s) to the original state (ground state) (Fig. 5.1a). Emission proceeds spontaneously after absorption - the time lapse between excitation and emission is negligibly small in the case of fluorescence - at a longer wavelength. The absorption spectrum and the fluorescence spectrum are often almost mirror images of each 

The emission of fluorescence light quanta may be suppressed by fluorescence quenching. In such cases, excitation energy 

Fluorescence spectroscopy is often used for detection of atoms and molecules. Laser light is increasingly used for excitation (LIF Laser-induced fluorescence). 

---

Bibliography and Notes for Chapter 5 Photophysical properties of dendritic molecules ... 

---