Results 61 to 70 of about 9,652 (250)

The interplay of different relaxation channels in the excited state dynamics of photoinitiators

EPJ Web of Conferences, 2013
Different photoinitiators are investigated by femtosecond transient absorption spectroscopy and DFT calculations. Their initiation properties are critically governed by competition between intersystem crossing, fluorescence and internal conversion partly
Barner-Kowollik C., Wegener M., Voll D., Fischer J., Wolf T. J. A., Unterreiner A.-N.   +5 more
doaj   +1 more source

Understanding H-aggregates crystallization induced emissive behavior: insights from theory

Scientific Reports, 2023
We conducted a theoretical investigation into how the molecular stacking effect impacts the photophysical properties in solid phases. Our findings indicated that in the aggregated state, the out-of-plane distorted vibration and imidazole ring stretching ...
Huixue Li, Lingling Lv, Kun Yuan, Sujuan Pan, Zhifeng Li   +4 more
doaj   +1 more source

Origin of Enhanced Efficiency and Reduced Roll‐Off in Organic Light‐Emitting Diodes Based on Pt(II) Complexes

Advanced Science, EarlyView.
Controlled Pt–Pt fine structure in square‐planar Pt(II) complexes governs metal–metal‐to‐ligand charge‐transfer (MMLCT) state formation, exciton dynamics, and organic light‐emitting diode performance. Short Pt–Pt contacts in Pt(fppz)2 enable coherent metal–metal coupling, sub‐microsecond emission and an external quantum efficiency of 29%, whereas ...
Atul Shukla, Sarah K. M. McGregor, Julian A. Steele, Innes K. Gale, Kiyoshi Miyata, Monirul Hassan, Christian McDonald, Romain J. Lepage, Eduardo Solano, Pilankatta K. Ramya, Cherumuttathu H. Suresh, Takumi Ehara, Chihaya Adachi, Ken Onda, Shih‐Chun Lo, Ebinazar B. Namdas   +15 more
wiley   +1 more source

1‐Azabicyclo[1.1.0]butanes (ABBs) on the Map: Mechanistic Pathways for Catalytic Ring Opening and Functionalizations

Angewandte Chemie, EarlyView.
Catalytic strain‐release ring opening and functionalizations of 1‐azabicyclo[1.1.0]butanes (ABBs) represent a promising strategy for accessing diverse azetidine products. These transformations proceed via polar pathways, radical pathways, and hybrid mechanisms that combine both.
James Shao‐Jiun Yang, Hsuan‐Hung Liao   +1 more
wiley   +2 more sources

Spin Photochemistry: Electron Spin Multiplicity as a Tool for Reactivity and Selectivity Control

CHIMIA, 2021
Spin chemistry involving small organic molecules without heavy atoms is highly sensitive to spin-orbit-coupling (SOC) modulating biradical conformation as well as hyperfine coupling (HFC) modulating magnetic isotope interactions. Several easily available
Axel G. Griesbeck, Seyma Bozkus
doaj   +1 more source

Aggregation‐Controlled Triplet Exciton Regulation Enables Single‐Emitter Color‐Evolving Afterglow

Advanced Science, EarlyView.
A single‐emitter system based on DTP‐R luminophores enables time‐evolving afterglow through aggregation‐regulated excited‐state dynamics. The coexistence and suppression of delayed fluorescence and phosphorescence are controlled via concentration tuning and host‐guest engineering, revealing the RISC origin of delayed fluorescence and enabling ...
Yu Zhang, Zonghang Liu, Gian Albert Alfani, Xilong Wei, Yue Zhang, Ziyu Cui, Yi Lu, Yixuan Chen, Dan Liu, Lin Lu, Zihao Deng, Shuyu Xue, Parvej Alam, Zheng Zhao, Ben Zhong Tang   +14 more
wiley   +1 more source

The phthalocyanines applications in photodynamic therapy investigated by time-resolved and steady-state photothermal methods

International Journal of Photoenergy, 2002
The time-resolved photothermal methods are used in order to establish the yield of intersystem (singlet-triplet) crossing of dyes that are candidates for the application in photodynamic therapy.
Danuta Frackowiak, Krzysztof Wiktorowicz, Alfons Planner, Aneta Waszkowiak, Rodica-Mariana Ion   +4 more
doaj   +1 more source

Photoactivation‐Enabled Tunable Room‐Temperature Phosphorescence and Thermally Activated Delayed Fluorescence in Crystalline Materials

Advanced Science, EarlyView.
This work is the first to demonstrate the regulation of photoactivated room‐temperature phosphorescence (RTP) and thermally activated delayed fluorescence (TADF) in crystalline materials without any pretreatment. Furthermore, we reveal the underlying mechanisms by uncovering the role of host‐guest energy level alignment, exciton lifetime, crystallinity,
Lisha Zhang, Yongping Wu, Ihor Sahalianov, Lei Zhou, Glib Baryshnikov, Xiang Ma   +5 more
wiley   +1 more source

Excited-State Dynamics of the Thiopurine Prodrug 6-Thioguanine: Can N9-Glycosylation Affect Its Phototoxic Activity?

Molecules, 2017
6-Thioguanine, an immunosuppressant and anticancer prodrug, has been shown to induce DNA damage and cell death following exposure to UVA radiation. Its metabolite, 6-thioguanosine, plays a major role in the prodrug’s overall photoreactivity.
Brennan Ashwood, Steffen Jockusch, Carlos E. Crespo-Hernández   +2 more
doaj   +1 more source

Photorelaxation Pathways of 4-(N,N-Dimethylamino)-4′-nitrostilbene Upon S₁ Excitation Revealed by Conical Intersection and Intersystem Crossing Networks

Molecules, 2020
Multi-state n-electron valence state second order perturbation theory (MS-NEVPT2) was utilized to reveal the photorelaxation pathways of 4-(N,N-dimethylamino)-4′-nitrostilbene (DANS) upon S1 excitation.
Ziyue He, Ruidi Xue, Yibo Lei, Le Yu, Chaoyuan Zhu   +4 more
doaj   +1 more source