Full metadata record
DC FieldValueLanguage
dc.contributor.authorLi, SWen_US
dc.contributor.authorCheng, YMen_US
dc.contributor.authorYeh, YSen_US
dc.contributor.authorHsu, CCen_US
dc.contributor.authorChou, PTen_US
dc.contributor.authorPeng, SMen_US
dc.contributor.authorLee, GHen_US
dc.contributor.authorTung, YLen_US
dc.contributor.authorWu, PCen_US
dc.contributor.authorChi, Yen_US
dc.contributor.authorWu, FIen_US
dc.contributor.authorShu, CFen_US
dc.date.accessioned2014-12-08T15:18:12Z-
dc.date.available2014-12-08T15:18:12Z-
dc.date.issued2005-10-21en_US
dc.identifier.issn0947-6539en_US
dc.identifier.urihttp://dx.doi.org/10.1002/chem.200500434en_US
dc.identifier.urihttp://hdl.handle.net/11536/13159-
dc.description.abstractThe rational design and syntheses of a new series of Os-II complexes with formula [Os(fppz)(2)(CO)(L)] (1: L=4-dimethylaminopyridine; 2: L=pyridine; 3: L = 4,4'bipyridine; 4: L=pyridazine; 5: L = 4-cyanopyridine), bearing two (2-pyridyl)pyrazolate ligands (fppz) together with one carbonyl and one N-heterocyclic ligand at the axial positions are reported. Single-crystal X-ray diffraction studies of, for example, 2 reveal a distorted octahedral geometry in which both fppz ligands reside in the equatorial plane with a trans configuration and adopt a bent arrangement at the metal center with a dihedral angle of similar to 23 degrees, while the carbonyl and pyridine ligands are located at the axial positions. Variation of the axial N-heterocyclic ligand leads to remarkable changes in the photophysical properties as the energy gap and hence the phosphorescence peak wavelength can be tuned. For complexes 1 and 2 the solvent-polarity-independent phosphorescence originates from a combination of intraligand (3)pi-pi* ((ILCT)-I-3) and metal-to-ligand charge transfer transitions ((MLCT)-M-3). In sharp contrast, as supported by cyclic voltammetry measurements and theoretical calculations, complexes 3-5 exhibit mainly ligand-to-lilgand charge transfer (LLCT) transitions, resulting in a large dipolar change. The phosphorescence of complexes 3-5 thus exhibits a strong dependence on the polarity of the solvent, being shifted for example, from 560 (in C6H12) to 665 nm (in CH3CN) and from 603 (in C6H12) to 710 nm (in CH3CN) for complexes 3 and 5, respectively. The results clearly demonstrate that a simple, straightforward derivatization of the axial N-heterocyclic ligand drastically alters the excitation properties per se from intraligand charge transfer (ILCT) to LLCT transitions. The latter exhibit remarkable LLCT phosphorescence solvatochromism so that a broad range of color tunability can be achieved.en_US
dc.language.isoen_USen_US
dc.subjectcharge transferen_US
dc.subjectN ligandsen_US
dc.subjectosmiumen_US
dc.subjectphosphorescenceen_US
dc.subjectsolvatochromismen_US
dc.titleInterplay between intra- and interligand charge transfer with variation of the axial N-heterocyclic ligand in osmium(II) pyridylpyrazolate complexes: Extensive color tuning by phosphorescent solvatochromismen_US
dc.typeArticleen_US
dc.identifier.doi10.1002/chem.200500434en_US
dc.identifier.journalCHEMISTRY-A EUROPEAN JOURNALen_US
dc.citation.volume11en_US
dc.citation.issue21en_US
dc.citation.spage6347en_US
dc.citation.epage6357en_US
dc.contributor.department應用化學系zh_TW
dc.contributor.departmentDepartment of Applied Chemistryen_US
dc.identifier.wosnumberWOS:000232960500023-
dc.citation.woscount18-
Appears in Collections:Articles


Files in This Item:

  1. 000232960500023.pdf

If it is a zip file, please download the file and unzip it, then open index.html in a browser to view the full text content.