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Title: Excited state processes of dinuclear Pt( ii ) complexes bridged by 8-hydroxyquinoline
Dinuclear d 8 Pt( ii ) complexes, where two mononuclear square planar Pt( ii ) units are bridged in an “A-frame” geometry, possess photophysical properties characterised by either metal-to-ligand-(MLCT) or metal–metal–ligand-to-ligand charge transfer (MMLCT) transitions determined by the distance between the two Pt( ii ) centres. When using 8-hydroxyquinoline (8HQH) as the bridging ligand to construct novel dinuclear complexes with general formula [C^NPt(μ-8HQ)] 2 , where C^N is either 2-phenylpyridine (1) or 7,8-benzoquinoline (2), triplet ligand-centered ( 3 LC) photophysics results echoing that in a mononuclear model chromophore, [Pt(8HQ) 2 ] (3). The lengthened Pt–Pt distances of 3.255 Å (1) and 3.243 Å (2) results in a lowest energy absorption centred around 480 nm assigned as having mixed LC/MLCT character by TD-DFT, mirroring the visible absorption spectrum of 3. Additionally, 1 and 2 exhibit 3 LC photoluminescence with limited quantum yields (0.008) from broad transitions centred near 680 nm. Photoexcitation of 1–3 leads to an initially prepared excited state that relaxes within 15 ps to a 3 LC excited state centred on the 8HQ bridge, which then persists for several microseconds. All the experimental results correspond well with DFT electronic structure calculations.  more » « less
Award ID(s):
1955795
NSF-PAR ID:
10463568
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Dalton Transactions
Volume:
52
Issue:
13
ISSN:
1477-9226
Page Range / eLocation ID:
4008 to 4016
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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