| dc.description.abstract | Platinum(ll) terdentate and bidentate complexes possess square-planar d8 configuration.
The moderate metal-to-ligand charge-transfer (1MLCT) absorption, 3MLCT emission, and
broadband excited-state absorption are the unique spectroscopic features for these
complexes. In my thesis work, two series of terdentate platinum(II) complexes and one
bidentate platinum(II) complex were designed and synthesized. The photophysical
properties, such as the electronic absorption, photoluminescence, and triplet excited-state
absorption, are investigated systematically.
Chapter I introduced the representative work on the synthesis and photophysical
studies of the terdentate and bidentate platinum(II) complexes reported in the literature.
The motivation for my thesis project was briefly discussed. In Chapter 2, the synthesis and photophysical properties of two platinum 6-phenyl-4-
(9,9-dihcxylfluoren-2-yl)-2,2 '-bipyridine complexes with phenothiazinyl (PTZ) acetylide
ligand were discussed. Their UV-vis absorption and emission characteristics in solutions
and LB films were systematically investigated. The triplet transient difference absorption
and reverse saturablc absorption were also studied for these complexes. Both complexes
exhibit a broad metal-to-ligand charge-transfer / ligand-to-ligand charge-transfer /
intraligand charge-transfer (1MLCTi1LLCTi11LCT) absorption band between 400 and 500
nm and a 'MLCT/'ILClill",ll"' emission band at -594 nm at room temperature, which blue
shifts at 77 K. Both UV-vis absorption and emission spectra show negative solvatochromic effect. Both of the complexes also exhibit broad and moderately strong triplet transient
absorption from the near-UV to the near-IR spectral region. In addition, LB films of them
were prepared and characterized by AFM technique. The UV-vis absorption and emission
spectra of the LB films of them were also investigated and compared with those obtained in
solutions. In Chapter 3, the synthesis and photophysical studies of a series of platinum 6-phenyl-
4-(7-benzothiazolyl-9, 9-diethyltluoren-2-yl)-2,2' -bi pyridine complexes with different
acetylides ligands, such as, nitrophenyl acetylide, tluorenyl acetylide, and
benzothiazolyltluorenyl acetylide, were discussed. The complex bearing nitrophenyl
acetylide ligand exhibited quite distinct photophysical properties compared to the other two
complexes. In Chapter 4, one platinum bis(mesitylimino)acenaphthene complex was synthesized.
The lowest-energy absorption band was attributed to 1MLCT transitions, which was much
broader and red-shifted (extending from 490 nm to 800 nm) compared to those reported for
other diiminc Pt(II) complexes. | en_US |
