Three organic devices with different quantum well period were fabricated. The potential barrier layer and well layer for electrons were made of N,N'-diphenyl-N,N'-bis(1-napthyl)-1,1'-biphenyl 1-4,4'-diamine(NPB) and 4,4,N,N'-dicarbazolebiphenyl(CBP). The photoluminescence quenching of these three devices under changed reverse voltages were studied. Results showed that photoluminescence quenching of NPB layer occurs more quickly than that of CBP layer in the authors' devices. This is because that the effective electric field in NPB layer is higher than that in CBP layer. The excitons in NPB and CBP layer were easily to be dissociated when the quantum well period increased under the same reverse voltage. Since these three devices are type II quantum well structure, the excitons in these devices are not very stable.
Download full-text PDF |
Source |
---|
J Chem Theory Comput
January 2025
BIFOLD─Berlin Institute for the Foundations of Learning and Data, 10587 Berlin, Germany.
While machine learning (ML) models have been able to achieve unprecedented accuracies across various prediction tasks in quantum chemistry, it is now apparent that accuracy on a test set alone is not a guarantee for robust chemical modeling such as stable molecular dynamics (MD). To go beyond accuracy, we use explainable artificial intelligence (XAI) techniques to develop a general analysis framework for atomic interactions and apply it to the SchNet and PaiNN neural network models. We compare these interactions with a set of fundamental chemical principles to understand how well the models have learned the underlying physicochemical concepts from the data.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
Department of Chemistry, Center for BioAnalytical Chemistry, Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Tsinghua University, Beijing, 100084, China.
Single nanoparticle analysis is crucial for various applications in biology, materials, and energy. However, precisely profiling and monitoring weakly scattering nanoparticles remains challenging. Here, it is demonstrated that deep learning-empowered plasmonic microscopy (Deep-SM) enables precise sizing and collision detection of functional chemical and biological nanoparticles.
View Article and Find Full Text PDFChem Asian J
December 2024
Department of Chemistry, Indian Institute of Technology Tirupati, Tirupati, A.P 517619, India.
Visible-light absorbing metal-free organic dyes are of increasing demand for various optoelectronic applications because of their great structure-function tunability through chemical means. Several dyes also show huge potential in triplet photosensitization, generating reactive singlet oxygen. Understanding the structure-property relationships of many well-known fluorescein dyes is of paramount importance in designing next-generation energy efficient dyes, which is currently limited.
View Article and Find Full Text PDFJ Phys Chem A
January 2025
Astrophysik/I. Physikalisches Institut, Universität zu Köln, Köln 50937, Germany.
The methoxy radical, CHO, has long been studied experimentally and theoretically by spectroscopists because it displays a weak Jahn-Teller effect in its electronic ground state, combined with a strong spin-orbit interaction. In this work, we report an extension of the measurement of the pure rotational spectrum of the radical in its vibrational ground state in the submillimeter-wave region (350-860 GHz). CHO was produced by H-abstraction from methanol using F atoms, and its spectrum was probed in absorption using an association of source-frequency modulation and Zeeman modulation spectroscopy.
View Article and Find Full Text PDFJ Mol Model
January 2025
INIFTA, DQT, Sucursal 4, C. C. 16, 1900, La Plata, Argentina.
Quantum mechanics has proved to be suitable for the study of molecular systems. In particular, the Born-Oppenheimer approximation enables one to separate the motions of electrons and nuclei. In the case of diatomic molecules, this approximation leads to the so-called potential-energy function that provides the interaction between the two nuclei.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!