Optical properties dithiolenes

In particular, the synthesis and the electrical, magnetic, and optical properties of the title complexes will be concisely reviewed here. Other aspects, of no less importance, such as the reactivity of 1,2-dichalcogenolene complexes27 and the role of 1,2-dithiolene complexes in biology28 or in analytical chemistry29 have been recently reviewed and the reader is referred to the most recent publications for more information.30 52... 

With rich luminescent properties, long-lived CT excited states and a variety of bimolecular photochemical reaction pathways, the mixed-ligand square-planar diimine dithiolene complexes of d8 metal ions show great promise for solar-energy conversion, as luminescent probes or in photocatalytic applications. Complexes of this type have also received attention for the nonlinear optical properties, such as second harmonic generation, related to the MMLL CT excited state (14, 129). 

Finally, in Section IV dithiolene complexes with interesting optical properties, such as strong near-IR (NIR) absorption, nonlinear optical behavior, and the use of some dithiolene complexes for optical data storage will be reviewed. In Section V, attempts toward coupling conducting, and magnetic or optical properties will be discussed briefly. 

Finally, in addition to Sections II (electrical properties), III (magnetic properties), and IV (optical properties), Section V will be devoted to dithiolene complexes exhibiting coexisting or coupled properties (electrical and magnetic, or electrical and optical). 

Since Chapter 6 (352) in this volume is devoted to the luminescence and photochemistry of dithiolene complexes, these aspects will not be developed here. In this section, we restrict ourselves to the review of dithiolene complex-based compounds exhibiting optical properties, such as strong infrared (IR) absorption and second- and third-order nonlinear optical properties. In the last part of this section, we will review the use of some dithiolene complexes for optical data storage (printers, developer, CD-ROM, etc.). Contrary to what was observed throughout the two previous sections, no particular dithiolene complex really dominates the domain of the molecular materials exhibiting interesting optical properties. 

Miscelleanous related works on the optical properties of dithiolene complexes have been published, and will be cited here just for recollection photoconductivity (525, 526) photoelectrical conversion and photoswitching (420, 527-529) and photosensitive materials (530). 

Chapter 8 reviews the considerable work that has been done on solid-state systems. These systems combine the structural features of planar dithiolene complexes, wherein specifically discovered and/or designed ligands form complexes that coalesce into extended lattices, with unusual conductive, magnetic, and/or optical properties. The extensive interest in this field is nurtured by the truly unusual nature of the extended structures, which, in turn, clearly exploit some of the unique structural and electronic structural features of the simpler dithiolene complexes. 

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