Article
Chemistry, Inorganic & Nuclear
Lu Zhu, Chenwei Sha, Anqi Lv, Wang Xie, Kang Shen, Yumeng Chen, Guohua Xie, Huili Ma, Hongbo Li, Xiao-Chun Hang
Summary: Two tetradentate Pt(II) complexes with bulky-group hindrances were synthesized and investigated for their structural and blue phosphorescent properties. The results showed high photoluminescent quantum yields and excellent electroluminescent performances. Understanding the role of peripheral hindrances provides an effective approach to designing high-quality blue phosphorescent emitters.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Inorganic & Nuclear
Kaiyue Ye, Peili Wang, Minjie Li, Yuqi Hou, Jianzhang Zhao, Yan Wan
Summary: We synthesized a N boolean AND N Pt(II) bisacetylide complex with strong absorption of visible light (molar absorption coefficients epsilon=6.7x10(4) M-1 cm(-1) at 570 nm) and high singlet oxygen quantum yield (phi(Delta) = 78% ). The complex exhibits an intersystem crossing (ISC) of 81.8 ps and a triplet excited state lifetime of 7.6 μs. Density functional theory (DFT) calculations revealed that the S-1 and T-1 states are mainly localized on the perylenemonoimide (PMI) ligands, with noticeable involvement of the Pt(II) center. The complex acts as a triplet photosensitizer to generate delayed fluorescence with perylenebisimide (PBI) via triplet-triplet energy transfer (TTET) and triplet-triplet annihilation (TTA), resulting in a delayed fluorescence lifetime of 52.5 μs under the experimental conditions.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Jeffrey T. DuBose, Andrew Christy, Jishnudas Chakkamalayath, Prashant V. Kamat
Summary: The competition between energy transfer and charge trapping in 2D halide perovskite is studied, and sensitized emission is observed in bromide-rich compositions. Broad emission from trap states is observed at low temperatures.
Article
Chemistry, Multidisciplinary
Tobias Theiss, Stefan Buss, Ivan Maisuls, Rafael Lopez-Arteaga, Dana Bruenink, Jutta Koesters, Alexander Hepp, Nikos L. Doltsinis, Emily A. Weiss, Cristian A. Strassert
Summary: The synthesis, structure, and photophysical properties of two isoleptic bis-cyclometalated Pt(II) and Pd(II) complexes, [PtL] and [PdL], were reported. NMR spectroscopy and X-ray diffraction analysis confirmed the isostructural nature and intermolecular interactions of the complexes. Both complexes exhibited ligand-controlled aggregation, with the photophysical properties tunable through molecular design. The introduction of fluorine atoms and methoxy groups led to metal-metal interactions, resulting in luminescence from metal-perturbed ligand-centered or metal-metal-to-ligand charge-transfer triplet states.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Shunan Zhao, Jianfeng Song, Keith Man-Chung Wong
Summary: A series of platinum(ii) bipyridine complexes with two rhodamine-like alkynyl (Rhodyne) ligands were developed, demonstrating remarkable chemo-induced ON-OFF switching capabilities with near-infrared phosphorescence and delayed fluorescence. This study contributes to the design of versatile photosensitizers with multiple functionalities, including metal ion and biomolecule sensing, photodynamic therapy, and optoelectronics.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Misaki Kamioka, Yitong Wang, Shigeki Mori, Hiroyuki Furuta, Soji Shimizu
Summary: A sigma-bonded platinum(II) diketopyrrolopyrrole (Pt-DPP) complex with high fluorescence properties in both solution and solid state was synthesized. The intense emission of the Pt-DPP complex is attributed to the DPP-centered fluorescence. In the solid state, aggregation-caused quenching is mitigated by the well-segregated molecular packing due to the bulky triphenylphosphine ligands. The easy synthesis and unique fluorescence properties of the Pt-DPP complex are beneficial for the development of DPP-based functional chromophores.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2022)
Article
Materials Science, Multidisciplinary
Ru He, Charles J. Zeman, Rajendra Acharya, Kirk S. Schanze
Summary: Platinum(II) poly-ynes exhibit lower transient absorption compared to a molecular complex with the same structure. The diminished absorption is attributed to intrachain triplet-triplet annihilation resulting from the presence of multiple excitons in the polymer chains.
ACS APPLIED POLYMER MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Hannah Kurz, Konstantin Schoetz, Ilias Papadopoulos, Frank W. Heinemann, Harald Maid, Dirk M. Guldi, Anna Koehler, Gerald Hoerner, Birgit Weber
Summary: The study presents a family of planar nickel(II) complexes with sensitive CISSS tracked by fluorescence detection. These complexes fluoresce in noncoordinating solvents but are fluorescence-silent in the presence of axial ligands. FD-CISSS shows higher sensitivity compared to absorption-based CISSS.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Physical
Tongyu Zhao, Wenjun Ni, Christian Kloc, Licheng Sun, Gagik G. Gurzadyan
Summary: The study found that singlet fission (SF) can be directly observed in ICZ films, while SF and polaron formation compete in the ultrafast timescale in ICZ crystals.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Inorganic & Nuclear
Alexandre Abherve, Maurizio Mastropasqua Talamo, Sara Boi, Vincent Poupard, Frederic Gendron, Boris Le Guennic, Narcis Avarvari, Flavia Pop
Summary: The study presented a successful synthesis of a series of bipyridine-substituted DPPT ligands, revealing their properties in solid state and solution through photophysical and structural characterization. The research opens up new possibilities for organic electronic applications.
INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Takatoshi Maeda, Taizo Mori, Masahiro Ikeshita, Shing Cho Ma, Gilles Muller, Katsuhiko Ariga, Takeshi Naota
Summary: This study reports the precise control of circularly polarized luminescence (CPL) under vortex flow conditions at an air-water interface. The vortex flow induces and controls the supramolecular chirality of aggregates, allowing for precise adjustment of the CPL direction and magnitude.
Article
Biochemistry & Molecular Biology
Stefan Buss, Leon Geerkens, Maria Victoria Cappellari, Alexander Hepp, Jutta Koesters, Cristian A. Strassert
Summary: This study investigates the impact of auxiliary ligands on the photophysical properties of Pt(II) complexes and demonstrates that the properties of the auxiliary ligands have some influence on the photoluminescence characteristics, but cannot significantly improve the photoluminescence quantum yield at room temperature.
Article
Chemistry, Multidisciplinary
Wiebke Alex, Patrick Lorenz, Christian Henkel, Timothy Clark, Andreas Hirsch, Dirk M. Guldi
Summary: This study provides a detailed understanding of the full reaction coordinate of NBDs to QCs and reveals that the photoreversibility of NBDs is influenced by the charge-transfer character.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Inorganic & Nuclear
Joseph J. Mihaly, Steven M. Wolf, Alexis T. Phillips, Sokhalita Mam, Zheng Yung, Joy E. Haley, Matthias Zeller, Kimberly de la Harpe, Ethan Holt, Tod A. Grusenmeyer, Stephanie Collins, Thomas G. Gray
Summary: The syntheses and photophysical characterization of five new gold(I) complexes with diphenylamine-substituted fluorenyl moieties were reported. The complexes exhibited vibronically structured absorption and luminescence bands, which were attributed to pi-pi* transitions localized on the diphenylamine-substituted fluorenyl pi system. The excited-state dynamics of these chromophores were influenced by the selection of ancillary ligand and sigma attachment of the diphenylamine-substituted fluorenyl moiety.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Souvik Mandal, Chantal Daniel
Summary: The absorption spectrum of [Pt(dpybMe)Cl] has been revisited using non-adiabatic wavepacket quantum dynamics. It is shown that the vibronic structure observed in the experimental spectrum is caused by the in-plane scissoring and rocking motions of the cyclometalated tridentate ligand. The ultrafast decay of [Pt(dpybMe)Cl] is governed by spin-vibronic mechanism and is influenced by various factors such as excited state electronic characters and spin-orbit and active tuning mode interplay.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Kameel Antami, Fazel Bateni, Mahdi Ramezani, Cory E. Hauke, Felix N. Castellano, Milad Abolhasani
Summary: This study introduces the in-flow hot injection synthesis method for cesium lead iodide nanocrystals, providing a comprehensive understanding of the competing reaction parameters controlling the morphology and properties of the nanocrystals. It reveals a change in the CsPbI3 formation mechanism at temperatures above 150 degrees C and demonstrates the deficiencies of batch reactors in reproducible and scalable synthesis of CsPbI3 nanocrystals. The developed modular flow chemistry route opens up new possibilities for high-temperature studies of solution-processed nanocrystals and enables consistent and reliable continuous nanomanufacturing for next-generation energy technologies.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Alexander Reichle, Hannes Sterzel, Peter Kreitmeier, Remi Fayad, Felix N. Castellano, Julia Rehbein, Oliver Reiser
Summary: The study showcases the concept of light-induced homolysis for radical generation in Cu-II-photocatalyzed decarboxylative oxygenation. Two Cu-II-carboxylate complexes with different coordination geometries were synthesized and characterized by X-ray analysis, correlating their structure with their ability to initiate light-induced decarboxylations.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Inorganic & Nuclear
Subhangi Roy, Antonio A. Lopez, James E. Yarnell, Felix N. Castellano
Summary: The study presented the investigation of two distinct species of square planar dinuclear Pt(II) dimers based on anti-[Pt(C^N)(mu-N^S)](2), showcasing their potential for promoting light-energized chemical reactions through their visible absorbing chromophores.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Xingao Zhang, Margaret H. Hudson, Felix N. Castellano
Summary: Utilizing triplet excitons in semiconductor quantum dots in conjunction with surface-anchored molecules to produce long-lifetime thermally activated delayed photoluminescence (TADPL) has promising applications in various fields, but the presence of toxic metals in most QDs limits their real-world use. Newly conceived InP quantum dot nanomaterials interfaced with different naphthoic acid ligands exhibit distinct lifetime ranges and regulated photophysical properties, suggesting the potential for discovering new nanomaterials with TADPL capabilities.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Paul T. Cesana, Beryl X. Li, Samuel G. Shepard, Stephen Ting, Stephanie M. Hart, Courtney M. Olson, Jesus I. Martinez Alvarado, Minjung Son, Talia J. Steiman, Felix N. Castellano, Abigail G. Doyle, David W. C. MacMillan, Gabriela S. Schlau-Cohen
Summary: By mimicking the modular structure of photosynthesis, attaching R-phycoerythrin to a transition metal photocatalyst has increased the efficiency of the biohybrid photocatalyst. Experimental results demonstrate a significant increase in yields for reactions at red wavelengths using the biohybrid photocatalyst.
Article
Chemistry, Inorganic & Nuclear
Anitha S. Gowda, Tia S. Lee, Michael C. Rosko, Jeffrey L. Petersen, Felix N. Castellano, Carsten Milsmann
Summary: This article reports the synthesis of three stable group 14 compounds that can access long-lived triplet excited states using their significant spin-orbit coupling constants. These compounds exhibit efficient photoluminescence properties with competing prompt fluorescence and thermally activated delayed fluorescence at and around room temperature.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Xingao Zhang, Felix N. Castellano
Summary: Researchers successfully addressed the challenge of observing TADPL in InP QDs caused by electron trap states by using the heterocyclic aromatic compound QCA. They found that QCA-functionalized InP QDs can generate bright-state TADPL through energy transfer between photoexcited InP QDs and surface-anchored QCA chromophores.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Emily E. Brown, Iuliia Mandzhieva, Patrick M. TomHon, Thomas Theis, Felix N. Castellano
Summary: In this study, a established photosensitizer was used to sensitize the triplet ligand-field states in a transition metal catalyst, resulting in successful hyperpolarization. This method provides an important experimental means for studying light activation in transition metal catalysts with low-lying triplet ligand-field states.
ACS CENTRAL SCIENCE
(2022)
Article
Chemistry, Multidisciplinary
Denis Leshchev, Andrew J. S. Valentine, Pyosang Kim, Alexis W. Mills, Subhangi Roy, Arnab Chakraborty, Elisa Biasin, Kristoffer Haldrup, Darren J. J. Hsu, Matthew S. Kirschner, Dolev Rimmerman, Matthieu Chollet, J. Michael Glownia, Tim B. van Driel, Felix N. Castellano, Xiaosong Li, Lin X. X. Chen
Summary: The trajectories of photoexcited molecules before thermalization play a crucial role in determining the outcome of photochemical reactions. By using femtosecond wide-angle X-ray solution scattering, the excited-state trajectories of a diplatinum complex with photoactivated metal-metal sigma-bond formation and Pt-Pt stretching motions were observed in real time. The observed motions coincide with the coherent vibrational wavepacket motions detected by femtosecond optical transient absorption. The identification of two key coordinates for intersystem crossing provides insights into the electronic transitions occurring on the time scales of measured vibrational motions, revealing ultrafast nonadiabatic or nonequilibrium processes involving multiple excited-state potential energy surfaces (PESs).
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Inorganic & Nuclear
Michael C. Rosko, Eli M. Espinoza, Sarah Arteta, Sarah Kromer, Jonathan P. Wheeler, Felix N. Castellano
Summary: In this study, four new copper(I) coordination complexes were synthesized and characterized. These complexes exhibit longer excited-state lifetimes and high photoluminescence quantum efficiencies. By adjusting the 2,9-substituents, the photophysical properties of these complexes can be tailored, providing new directions for the discovery of MLCT chromophores.
INORGANIC CHEMISTRY
(2023)
Article
Multidisciplinary Sciences
Amanda A. Volk, Robert W. Epps, Daniel T. Yonemoto, Benjamin S. Masters, Felix N. Castellano, Kristofer G. Reyes, Milad Abolhasani
Summary: AlphaFlow is a self-driven fluidic lab that enables autonomous discovery and optimization of complex multi-step chemistries through reinforcement learning. It successfully identified and optimized a novel multi-step reaction route that outperformed conventional sequences.
NATURE COMMUNICATIONS
(2023)
Article
Multidisciplinary Sciences
Shahnawaz Rafiq, Nicholas P. Weingartz, Sarah Kromer, Felix N. Castellano, Lin X. Chen
Summary: Design-specific control over the transitions between excited electronic states of different spin multiplicities is crucial. Previous studies have shown that the spin-vibronic effect can accelerate quantum-mechanically forbidden transitions at non-adiabatic crossings. However, identifying precise experimental manifestations of this mechanism has been challenging. In this study, coherence spectroscopy experiments reveal the interplay between spin, electronic, and vibrational degrees of freedom in driving efficient singlet-triplet conversion, shedding light on the spin-vibronic mechanism.
Article
Chemistry, Inorganic & Nuclear
Sarah Kromer, Subhangi Roy, James E. Yarnell, Chelsea M. Taliaferro, Felix N. Castellano
Summary: Dinuclear d(8) Pt(ii) complexes exhibit photophysical properties determined by the distance between the two Pt(ii) centres, showing either metal-to-ligand-(MLCT) or metal-metal-ligand-to-ligand charge transfer (MMLCT) transitions. The novel dinuclear complexes with 8-hydroxyquinoline as the bridging ligand possess similar photophysics to the mononuclear model chromophore. TD-DFT calculations confirm the mixed LC/MLCT nature of the lowest energy absorption and the limited quantum yields of the (LC)-L-3 photoluminescence for these complexes.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Dooyoung Kim, Michael C. Rosko, Vinh Q. Dang, Felix N. Castellano, Thomas S. Teets
Summary: One of the main challenges in developing effective copper(I) photosensitizers is their short excited-state lifetimes. In this study, steric modifications were introduced to improve the excited-state lifetimes of these complexes, and the effects of alkyl groups on the excited-state dynamics were investigated. The results revealed that sterically encumbered complexes exhibited significantly longer excited-state lifetimes compared to the unsubstituted complex.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Pyosang Kim, Andrew J. S. Valentine, Subhangi Roy, Alexis W. Mills, Felix N. Castellano, Xiaosong Li, Lin X. Chen
Summary: This study investigates the ultrafast excited state processes of a platinum complex, revealing the impact of Pt-Pt bond contraction on its optical properties.
FARADAY DISCUSSIONS
(2022)