Article
Chemistry, Physical
Chun-Li Song, Zheng Li, Jia-Rui Wu, Tong Lu, Ying-Wei Yang
Summary: This study reports on the photoluminescence properties of a macrocycle modified with donor-acceptor motifs. The macrocycle exhibits unexpected intramolecular through-space charge transfer and aggregation-induced emission properties, with the ratio of different emissions being easily affected by the environment. Additionally, the macrocycle also displays a pronounced color-changing behavior in the presence of common nitrile vapors with varying hydrocarbon chain lengths.
CHEMISTRY OF MATERIALS
(2022)
Article
Chemistry, Physical
Jiantao Leng, Tianquan Ying, Zhengrong Guo, Yingyan Zhang, Tienchong Chang, Wanlin Guo, Huajian Gao
Summary: This study proposes a general principle to achieve continuous water flow in long nanochannels and introduces a method involving the building of cascading driving units with net thermal gradient force. The study shows that within a single driving unit, the net thermal gradient force can be achieved through multiple strategies, including geometrical, mechanical, electrical, and chemical approaches. The proposed method has fundamental significance for nanofluidic systems and potential applications in nanoscale mass transport and energy conversion devices.
Article
Materials Science, Multidisciplinary
Maxim E. Sideltsev, Alexey A. Piryazev, Azalia F. Akhkiamova, Mikhail V. Gapanovich, Denis V. Anokhin, Diana K. Sagdullina, Alexander S. Novikov, Dimitri A. Ivanov, Alexander V. Akkuratov
Summary: This article reports the synthesis of two novel donor-acceptor small molecules BBT-H and BBT-F, and investigates the impact of morphology rearrangement upon thermal annealing on hole-transport characteristics of thin films based on them. It is shown that morphological changes occurring upon annealing of thin films based on fluorine-containing molecule BBT-F result in a spectacular enhancement of hole mobilities, while hole mobilities of nonfluorinated BBT-H do not show any considerable changing. This effect highlights the importance of molecular engineering for the design of promising conjugated small molecules (CSMs) for next-generation thin-film electronics.
PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Xue-Qi Wang, Sheng-Yi Yang, Qi-Sheng Tian, Cheng Zhong, Yang-Kun Qu, You-Jun Yu, Zuo-Quan Jiang, Liang-Sheng Liao
Summary: Multi-layer pi-stacked emitters based on spatially confined D/A/D patterns have been developed to achieve high-efficiency TADF. Dual donor moieties and a single acceptor moiety are introduced to form 3D emitters, resulting in high PLQYs, small Delta E-ST, and fast RISC processes. Devices based on these emitters exhibit maximum EQEs higher than their D/A-type analogues.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Physical
Kai Zhang, Jianzhong Fan, Chuan-Kui Wang, Lili Lin
Summary: The study investigates the light-emitting properties of a T-shaped molecule pTPA-DPPZ compared to a Y-shaped molecule oTPA-DPPZ, and finds that pTPA-DPPZ has superior properties such as reduced energy gap, red-shifted emission, enhanced transition dipole moment and radiative rate, as well as suppressed non-radiative energy loss. Additionally, pTPA-DPPZ exhibits larger spin-orbit coupling constant and a smaller energy gap between T-2 and S-1, resulting in a superior TADF emission with balanced charge transport properties.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Polymer Science
Ken Albrecht, Eri Hisamura, Minori Furukori, Yasuo Nakayama, Takuya Hosokai, Kohei Nakao, Hiroki Ikebe, Akira Nakayama
Summary: Carbazole dendrimers with bulky terminal substituents and a benzophenone core were synthesized and studied for their thermally activated delayed fluorescence (TADF) properties. The results showed that the choice of substituents directly affected the fluorescence emission and the triplet energy, which correlated with the TADF efficiency. Simple terminal modifications could minimize intermolecular interactions and tune the on-off behavior of TADF.
Article
Green & Sustainable Science & Technology
Sungyup Jung, Minyoung Kim, Kun-Yi Andrew Lin, Young-Kwon Park, Eilhann E. Kwon
Summary: This study proposes a direct valorization platform for converting bio-heavy oil into biodiesel via thermally induced transesterification, achieving high biodiesel yield without catalyst, which enhances production efficiency and economic benefits.
JOURNAL OF CLEANER PRODUCTION
(2021)
Article
Chemistry, Multidisciplinary
Shahidul Alam, Haya Aldosari, Christopher E. Petoukhoff, Tomas Vary, Wejdan Althobaiti, Maryam Alqurashi, Hua Tang, Jafar I. Khan, Vojtech Nadazdy, Peter Mueller-Buschbaum, Gregory C. Welch, Frederic Laquai
Summary: This study investigates the thermally-induced degradation of organic photovoltaic devices and its effect on their optical properties, photophysics, and morphology. The results show that the degradation limits the open-circuit voltage and fill factor of the devices, while the short-circuit current density is only slightly affected. Energy-resolved electrochemical impedance spectroscopy measurements reveal a higher energy barrier for charge transfer in the degraded samples. Furthermore, the study finds that field-dependent charge generation significantly limits device performance.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Seif Alwan, Yonatan Dubi
Summary: This study presents a theory for the CISS effect based on the interplay between spin-orbit interactions in the electrode, the chirality of the molecule, and spin-transfer torque at the molecule-electrode interface. The theory can qualitatively account for key experimental observations and provides a set of predictions that can be readily tested experimentally.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Engineering, Electrical & Electronic
S. E. Parsa, J. C. Canadas, J. A. Diego, M. Mudarra, J. Sellares
Summary: In this study, measurements of PET electret samples using PEA and TSDC techniques were compared. The samples with activated alpha or rho relaxation showed uniform polarization and image charge on the electrodes. Different electrode configurations were tested when injecting external charge carriers into the samples. Differences in TSDC spectra were explained by the blocking behavior of the electrodes. Overall, PEA combined with TSDC proved to be a useful technique for studying thermally poled electrets.
JOURNAL OF ELECTROSTATICS
(2022)
Article
Chemistry, Multidisciplinary
Peng-Yan Fu, Bao-Ning Li, Qiang-Sheng Zhang, Jun-Ting Mo, Shi-Cheng Wang, Mei Pan, Cheng-Yong Su
Summary: In this study, a coordination polymer with ESIPT properties was synthesized, and the switching between thermally activated fluorescence and long persistent luminescence was achieved by controlling the temperature. The mechanism of ISC/RISC energy transfer in the coordination polymer was revealed, providing a new pathway for the design and application of advanced optical materials in the future.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Shuai Chen, Samir H. Al-Hilfi, Guangbo Chen, Heng Zhang, Wenhao Zheng, Lucia Di Virgilio, Jaco J. Geuchies, Junren Wang, Xinliang Feng, Andreas Riedinger, Mischa Bonn, Hai I. Wang
Summary: Thermal annealing is shown to be an effective strategy for controlling the optical and electrical properties of CdSe nanoplatelet solids. By tuning the inter-NPL distance through the thermal decomposition of ligands, enhanced electronic coupling is achieved, leading to increased efficiency in free carrier generation and conduction in NPL solids.
Article
Chemistry, Multidisciplinary
Wanlin Cai, Cheng Zhong, De-Yin Wu
Summary: To improve the visual quality and develop high-resolution displays, organic light-emitting diodes (OLEDs) with high color purity have gained attention. The color purity of OLEDs is determined by the vibronic coupling of emitters between the ground and emitting states. This study conducted theoretical analyses of the reorganization energy of B, O-doped polycyclic aromatic compounds with multi-resonance thermally activated delayed fluorescence (MR-TADF) to understand the variations in color purity.
MATERIALS CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Applied
Yangyang Huang, Dong-Hai Zhang, Xiao-Dong Tao, Zhuangzhuang Wei, Shanshan Jiang, Lingyi Meng, Ming-Xue Yang, Xu-Lin Chen, Can-Zhong Lu
Summary: Thermally activated delayed fluorescence (TADF) materials with through-space charge transfer (TSCT) have attracted extensive attention recently. In this study, two triptycene-derived TADF molecules with ortho-donor (D)-acceptor (A) conformations were designed and characterized. These emitters exhibited unique V-shaped face-to-face D-A alignments with significant intramolecular D-A interactions, enabling TSCT in addition to throughbond charge transfer (TBCT). The emitters also showed excellent thermal stability and high film-formation quality due to the rigid 3D triptycene scaffold. The doped OLEDs utilizing these emitters achieved high external quantum efficiencies up to 20.5%.
Review
Materials Science, Multidisciplinary
Qin Xue, Guohua Xie
Summary: Charge transfer is crucial in governing exciton dynamics in organic emitters, particularly in thermally activated delayed fluorescence (TADF) emitters. It plays a role in shaping radiative decays of excitons and modulating luminescent properties. Through-space charge transfer is found to be effective in changing emissive colors, exciton lifetimes, and quantum yields in OLEDs.
ADVANCED OPTICAL MATERIALS
(2021)
Article
Chemistry, Physical
Henning Kirchberg, Abraham Nitzan
Summary: This study considers a molecular junction immersed in a solvent, where the electron transfer occurs through Marcus-type steps. It is found that although the charge transfer is continuous, the solvent does not reach thermal equilibrium throughout the transport. By investigating the nonequilibrium solvent dynamics, the electrical, thermal, and thermoelectric properties of the molecular junction are examined. The results show that by tuning the friction, heat dissipation into the solvent can be reduced and heat transfer between the electrodes can be enhanced.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Mohammadhasan Dinpajooh, Abraham Nitzan
Summary: This work investigates the effect of stretching on the heat conduction of molecular junctions using nonequilibrium molecular dynamics simulations. The thermal conductance of these junctions is found to depend on the nature of metal leads and the stretching behavior is similar to pure polymeric structures. These findings suggest that the thermal conductivity under stretching is an intrinsic property of the polymer chain and not significantly influenced by interfacial structures.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Tao E. Li, Abraham Nitzan, Joseph E. Subotnik
Summary: In this study, the mechanism of polariton relaxation in liquid CO2 under weak external pumping is systematically investigated using classical cavity molecular dynamics (CavMD) simulations. The results show that polariton relaxation is a combination of cavity loss through the photonic component and dephasing of the bright-mode component to vibrational dark modes mediated by intermolecular interactions. The rate of polaritonic dephasing is proportional to the product of the weight of the bright mode in the polariton wave function and the spectral overlap between the polariton and dark modes, and is sensitive to parameters such as the Rabi splitting and cavity mode detuning. The CavMD simulations yield similar parameter dependence for the upper polariton relaxation lifetime compared to Fermi's golden rule calculation based on a tight-binding harmonic model, but sometimes show modest disagreement for the lower polariton. The authors suggest that this discrepancy may be due to polariton-enhanced molecular nonlinear absorption caused by molecular anharmonicity, which is not accounted for in the analytical model. Recent progress on probing nonreactive VSC dynamics with CavMD is also summarized.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Monosij Mondal, Maicol A. Ochoa, Maxim Sukharev, Abraham Nitzan
Summary: The interaction between excited states of a molecule and excited states of a metal nanostructure leads to hybrid states with modified optical properties. The condition for strong coupling between plasmons and molecules can be easily satisfied if the only contributions to the spectral width are associated with the radiative and nonradiative relaxation of a single molecular vibronic transition. However, the observation of Rabi splitting becomes more challenging when the molecule-metal surface distance is varied due to the spectral shift associated with the same molecule-plasmon interaction.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Tao E. Li, Abraham Nitzan, Sharon Hammes-Schiffer, Joseph E. Subotnik
Summary: This study presents a quantum simulation of vibrational strong coupling in the collective regime using thermostated ring-polymer molecular dynamics. The simulation shows that including nuclear and photonic quantum effects does not change the Rabi splitting but broadens polaritonic line widths. Additionally, both quantum and classical simulations predict that the static dielectric constant of liquid water remains largely unchanged inside vs outside the cavity under thermal equilibrium. However, this disagrees with a recent experiment, suggesting potential limitations of the approach or unexplored experimental factors.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Physical
Bingyu Cui, Abraham Nizan
Summary: This study investigates the implications of the collective optical response of molecular ensembles in optical cavities on molecular vibronic dynamics. The results suggest that strong molecule-radiation field coupling can lead to polaron decoupled dynamics, but the observed dynamics mainly reflect the local nature of the electronic polariton.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Henning Kirchberg, Abraham Nitzan
Summary: In this study, the zero-frequency charge current noise and the thermodynamic uncertainty relation (TUR) in a metal-molecule-metal junction in a thermal environment were investigated using a classical master equation. The researchers found that the classical current noise had a similar structure to its quantum analog and determined the bound on the entropy production in an electrochemical junction in the Marcus regime. The same methodology was also applied to predict the upper bound for the efficiency of energy conversion in a prototype photovoltaic cell.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Monosij Mondal, Alexander Semenov, Maicol A. Ochoa, Abraham Nitzan
Summary: Controlling molecular spectroscopy and chemical behavior in a cavity environment is a hot topic. Plasmonic cavities can have strong radiation-matter coupling, even at the level of single molecules. This study presents a method for estimating the radiation-matter coupling and applies it to the calculation of infrared cavities.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Physical
Maxim Sukharev, Joseph Subotnik, Abraham Nitzan
Summary: This study examines the photodissociation dynamics of an ensemble of diatomic molecules resonantly coupled to a resonant optical cavity under strong coupling conditions at normal incidence. The coupled Maxwell-Schrodinger equations are numerically integrated to account for the molecular ro-vibrational degrees of freedom. It is shown that driving the system at its polaritonic frequencies significantly affects and slows down the dissociation, with no classical analog. An intuitive explanation for the dissociation slowdown at polaritonic frequencies is proposed.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Natalya A. A. Zimbovskaya, Abraham Nitzan
Summary: In this study, the effect of chain configuration on phonon heat transport in a single polymer chain is analyzed theoretically based on recent molecular dynamic simulations. It is found that when the chain is strongly compressed and tangled, multiple random bends act as scattering centers for vibrational phonon modes, resulting in diffusive heat transport. As the chain straightens up, the number of scatterers decreases and the heat transport becomes more ballistic. A model of a long atomic chain is introduced to simulate the changes in chain configuration, and the phonon thermal conductance exhibits a threshold-like transition from diffusive to ballistic transport as the scatterers are gradually removed.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Galen T. Craven, Abraham Nitzan
Summary: Theoretical investigation on the thermal transport properties resulting from electron transfer in a molecular conduction junction reveals that the properties can significantly vary based on the characteristics of the molecular bridge and its environment. The system's thermal conductance commonly deviates from Fourier's law, and in properly engineered systems, the electron hopping thermal conductance is similar to that measured in single-molecule devices.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Bingyu Cui, Maxim Sukharev, Abraham Nitzan
Summary: This work investigates the quantum mechanical description of the interaction between photons and molecules. Approximation schemes, such as perturbation theory and mean-field Hartree approximation, are commonly used. The truncated 1-exciton model is found to be suitable for strong coupling approximation, and its results agree well with semiclassical mean-field calculations in several prototype problems.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Bingyu Cui, Maxim Sukharev, Abraham Nitzan
Summary: Similar to a free particle, a broad wavepacket on an ordered lattice initially grows slowly and eventually spreads linearly with time. However, on a disordered lattice, the growth is inhibited for a long time due to Anderson localization. Through numerical simulations and analytical studies, we demonstrate that the short-term growth of particle distribution is faster on a disordered lattice than on an ordered one. This faster spread may have relevance to exciton motion in disordered systems.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Renai Chen, Mohammadhasan Dinpajooh, Abraham Nitzan
Summary: This study presents an atomistic simulation methodology for molecular heat conduction that incorporates quantum statistics and a modified Langevin equation to consider quantum effects. The results show that this quasi-classical method is suitable for the full temperature range and can simulate the effects of anharmonicity and high-frequency modes on heat conduction.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Annabelle Oz, Abraham Nitzan, Oded Hod, Juan E. Peralta
Summary: This study introduces a first-principles approach to describe electron dynamics in open quantum systems. By using time-dependent density functional theory on finite model systems and imposing open boundary conditions via the driven Liouville-von Neumann methodology, the analysis of non-equilibrium dynamics is achieved.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2023)
