Abstract
The structural and photophysical properties of tetradentate Pt(ppzOppz), Pt(ppzOpopy), Pt(ppzOczpy), and Pt(czpyOczpy) have been experimentally and theoretically explored. Single-crystal diffraction measurements provided accurate structural information. Electrochemical and photophysical characterizations revealed internal electronic energy levels in ground and excited states. (Time-dependent) Density functional theory calculation revealed electron distributions in transition processes of S0 → S1 and S1 → T1 → S0. Electronic transition study indicated that Pt(ppzOppz) demonstrated mixed MLCT/LC states and Pt(czpyOczpy) showed MLCT-dominated states in S1 and T1. Both Pt(ppzOpopy) and Pt(ppzOczpy) presented strong delocalized spin transition (DST) during intersystem crossing. Upon frame modification of Pt(ppzOczpy), we found that their S1 and T1 can be independently manipulated. These blue emitters showed a tunable and narrow emission band (the narrowest fwhm was 19 nm) with luminescence efficiency as high as 86%. The findings of the DST transition mode in the neutral Pt(II) complexes provide guidance for rational design of novel phosphorescent materials.
Original language | English |
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Pages (from-to) | 2285-2292 |
Number of pages | 8 |
Journal | Journal of Physical Chemistry Letters |
Volume | 9 |
Issue number | 9 |
DOIs | |
State | Published - May 3 2018 |
Externally published | Yes |
Funding
This work was supported by the Nanjing Tech University (NJU) & AAC Technologies collaborated funds 20161117 and the National Natural Science Foundation of China (Nos. 61605075, 11504168, NSFC-PSF 51661145021, 2015CB932200).