Intraligand charge transfer ILCT

It is also possible that coordination of a metal alters the electron affinity of a portion of the ligand, resulting in observation of absorption and emission from a eharge transfer state localized on the ligand (intraligand charge transfer, ILCT). ... 

Several reports have taken advantage of this unique property to design a variety of photoswitching systems in recent years.Moore and co-workers reported one particularly interesting example. The complexes in their study are yhc-Re(CO)3(bpy) chromophores linked by a styryl pyridine that attaches an amine or an azacrown ether group (see Scheme 4 for structures). The absorption spectra of these complexes feature an intense intraligand charge-transfer (ILCT) band, which can be removed by protonation of the amine or azacrown... 

CT Computed Tomographic ILCT Intraligand Charge Transfer... 

It is briefly mentioned that the situation for Pt(II) complexes with qol" and qtl" ligands is different, since in these compounds the lowest excited states result from intraligand-charge transfer transitions ( ILCT) with very small metal admixtures [195,315,318,319]. This class of compounds exhibits highly efficient red to infrared emissions. It is noted that these Pt(II) compounds are related to systems like Al(qol)3 [315,318,319], which are of great interest for light-emitting electroluminescent devices for flat panel display systems [320,321]. 

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