Article
Chemistry, Physical
Naresh Alaal, Kurt R. Brorsen
Summary: In this study, the multicomponent HCI method is extended to excited states with the implementation of second-order Epstein-Nesbet correction and a new procedure using the FGH method for calculating reference excitation energies. Benchmarking with protonic excitations of HCN and FHF- molecules shows that the excited-state multicomponent HCI method achieves similar accuracy to previous methods.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Engineering, Marine
Jiaqi Han, Zhen Wang
Summary: A new method based on perturbation method and Fredholm theory is proposed in this study to analytically solve the eigenvalues and eigenfunctions of nonuniform Euler-Bernoulli beam vibration. The study considers the variation of tension in vertical marine riser from top to bottom caused by gravity effect and provides the eigenvalues and eigenfunctions under boundary conditions. The effectiveness of the new method based on perturbation method is verified by comparing the asymptotic analytical results with classical results. The influence of the change of the bottom tension on the perturbation method is analyzed, and the results show that the new method provides better accuracy for higher order natural frequency.
Article
Chemistry, Physical
Ke Liao, Huanchen Zhai, Evelin Martine Christlmaier, Thomas Schraivogel, Pablo Lopez Rios, Daniel Kats, Ali Alavi
Summary: We present a theory for a DMRG algorithm that can solve for both the ground and excited states of non-Hermitian transcorrelated Hamiltonians and demonstrate its applications in molecular systems. The method involves including known physics in the Jastrow factor to accelerate the basis set convergence rate. By making minimal changes to the existing TI-DMRG algorithm, we are able to efficiently find the ground and excited states with improved accuracy compared to the original DMRG method.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2023)
Article
Chemistry, Physical
Moritz Bensberg, Markus Reiher
Summary: This study demonstrates how active orbital spaces can be consistently selected along reaction coordinates in a fully automated way. The approach combines the Direct Orbital Selection orbital mapping ansatz with the fully automated active space selection algorithm AUTOCAS, without the need for structure interpolation between reactants and products. The algorithm is demonstrated for the potential energy profile of the homolytic carbon-carbon bond dissociation and rotation around the double bond of 1-pentene in the electronic ground state, but it also applies to electronically excited Born-Oppenheimer surfaces.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Automation & Control Systems
Robert Viator, Braxton Osting
Summary: We investigate the Steklov eigenvalues of three-dimensional nearly spherical domains. Previous research has shown that these eigenvalues depend analytically on the domain perturbation parameter. In this study, we compute the first-order term of the asymptotic expansion using the Wigner 3-j symbols. We analyze the expansion and demonstrate the isoperimetric result that the volume-normalized \ell th Steklov eigenvalue is stationary for a ball when \ell is a perfect square.
SIAM JOURNAL ON CONTROL AND OPTIMIZATION
(2022)
Article
Chemistry, Physical
Jacek Szczepkowski, Marcin Gronowski, Anna Grochola, Wlodzimierz Jastrzebski, Michal Tomza, Pawel Kowalczyk
Summary: This study focuses on the excited electronic states of the strontium dimer and compares theoretical calculations with experimental results. The accuracy and limitations of the theoretical models are assessed, paving the way for future more accurate theoretical and experimental spectroscopic studies.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Chemistry, Physical
Jacek Szczepkowski, Marcin Gronowski, Anna Grochola, Wlodzimierz Jastrzebski, Michal Tomza, Pawel Kowalczyk
Summary: This study focuses on excited electronic states of the strontium dimer, comparing theoretical calculations with experimental results to evaluate the accuracy and limitations of the employed theoretical models. The research provides a foundation for future more accurate theoretical and experimental spectroscopic studies.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Engineering, Multidisciplinary
Roya Aliakbarisani, Abdorasoul Ghasemi, M. Angeles Serrano
Summary: This paper presents a link prediction method called Laplacian Perturbation Method (LPM) based on perturbation theory, which significantly improves prediction accuracy and outperforms other methods.
IEEE TRANSACTIONS ON NETWORK SCIENCE AND ENGINEERING
(2022)
Article
Chemistry, Physical
Andrii Shyichuk, Marek Krosnicki
Summary: We propose a universal approach to model IVCT and MMCT transitions between ions in solids. The method combines RASSCF/CASPT2/RASSI-SO calculations and DFT calculations, and is applied to study the energy storage and thermoluminescence properties of Pr activator and Ti, Zr, Hf codopants in cubic Lu2O3.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Chemistry, Organic
Xin Ma, Erlu Feng, Hanning Jiang, Victoria M. Boulos, Jinshan Gao, John J. Nash, Hilkka Kenttamaa
Summary: The gaseous 2,6-didehydropyridinium cation and its derivatives undergo proton transfer reactions from their lowest-energy excited triplet states, potentially due to unfavorable molecular orbital interactions in their singlet ground states. These cations have smaller singlet-triplet splittings compared to other analogues, likely due to reduced orbital overlap caused by the presence of a nitrogen atom. Both singlet and triplet states are believed to be generated upon formation of biradicals, with triplet states leading to faster proton transfer rates unless heavy atoms are present in the biradicals.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Alberto Baiardi, Anna Klara Kelemen, Markus Reiher
Summary: The DMRG[FEAST] method applies the FEAST algorithm in the density matrix renormalization group (DMRG) algorithm for optimizing both low- and high-energy eigenstates, overcoming limitations of existing advanced excited-state DMRG algorithms. The reliability of DMRG[FEAST] is demonstrated by calculating anharmonic vibrational excitation energies of molecules with up to 30 fully coupled degrees of freedom.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2022)
Article
Multidisciplinary Sciences
Miklos Ronto, Eli Pollak, Rocco Martinazzo
Summary: Ritz eigenvalues provide upper bounds for energy levels, while lower bounds require calculation of variances. Improved SCLBT method outperforms Temple's results, similar to Lehmann theory in lower bound quality and convergence.
SCIENTIFIC REPORTS
(2021)
Article
Chemistry, Physical
Luca Craciunescu, Eirik M. Liane, Adam Kirrander, Martin J. Paterson
Summary: In this study, the excited state van der Waals (vdW) potential energy surfaces (PESs) of the NO A(2)Sigma(+) + CO2 X-1 Sigma(+)(g) system were thoroughly investigated using advanced computational methods. The results show that the employed methods are efficient and cost-effective in predicting the depth of vdW wells. Furthermore, the study highlights the influence of multi-reference effects and long-range vdW surfaces on rotational energy transfer.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Engineering, Electrical & Electronic
Miloslav Capek, Lukas Jelinek, Michal Masek
Summary: This article utilizes point group theory to solve the issue of erroneous duality gap caused by symmetries in optimization problems. The problems are divided into two classes based on their predisposition to suffer from this deficiency. Examples show the elimination of the erroneous duality gap and the effectiveness of the treatment in various optimization problems of increasing complexity.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2021)
Article
Chemistry, Multidisciplinary
J. Patrick Zobel, Thomas Knoll, Leticia Gonzalez
Summary: The non-adiabatic dynamics of (VCl3)-Cl-III(ddpd) complex and its phosphorescence properties were studied, revealing that 1-2% of the system can remain stable for 10 picoseconds and exhibit phosphorescence. During the dynamics, nuclear motion mainly involves increasing metal-ligand bond distances and decreasing trans-coordinated ligand atom angles to drive transitions between different electronic states.
Article
Multidisciplinary Sciences
Alexander Teplukhin, Brian K. Kendrick, Susan M. Mniszewski, Sergei Tretiak, Pavel A. Dub
Summary: This work compares the performance of the Mukai QUBO solver and the Ocean qbsolv in solving the electronic structure problem and finds that the Mukai QUBO solver outperforms the Ocean qbsolv in terms of energy accuracy. This stimulates the further development of software for utilizing modern quantum annealers.
Article
Chemistry, Physical
Manav Bhati, Sergei A. Ivanov, Thomas P. Senftle, Sergei Tretiak, Dibyajyoti Ghosh
Summary: The study revealed a distinct charge transfer character for low-energy electronic excitations in non-stoichiometric QDs, which occurs between the core and surface due to the charge imbalance from inequivalent numbers of anionic and cationic atoms. This phenomenon results in optically dark low-energy transitions, especially in anion-rich QDs. Insights from this study establish relationships between optical properties and charge distributions in non-stoichiometric QDs, facilitating their tunability for various applications.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Chemistry, Multidisciplinary
Shreetu Shrestha, Xinxin Li, Hsinhan Tsai, Cheng-Hung Hou, Hsin-Hsiang Huang, Dibyajyoti Ghosh, Jing-Jong Shyue, Leeyih Wang, Sergei Tretiak, Xuedan Ma, Wanyi Nie
Summary: In this work, the authors investigated the carrier diffusion length in two-dimensional Ruddlesden-Popper perovskite single crystals using scanning photocurrent microscopy. They observed a long in-plane carrier diffusion length and attributed it to the dominating dissociated free carrier transport. The results suggest that semiconducting devices fabricated from RP perovskite single crystals can be as efficient as their 3D counterparts.
Article
Chemistry, Physical
Qiao-qiao Li, Luo Yan, Weibin Chu, Junjie He, Huanbo Luo, Thomas Frauenheim, Sergei Tretiak, Liujiang Zhou
Summary: Transition-metal perovskite chalcogenides (TMPCs) have shown great potential as lead-free alternatives to lead-halide perovskites for optoelectronic applications. In this study, the effects of Ti- and Se-alloying strategies on polaron behavior and carrier lifetimes in nonradiative recombination were systematically investigated. The results reveal that Ti alloying leads to the formation of localized small polarons, while Se alloying generates large polarons. Additionally, Se-alloying prolongs the nonradiative electron-hole recombination lifetime by up to 60% compared to pristine BaZrS3 material.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Physical
Xiaoyan Wu, Shizheng Wen, Huajing Song, Thomas Frauenheim, Sergei Tretiak, ChiYung Yam, Yu Zhang
Summary: This work presents an efficient nonadiabatic molecular dynamics simulation method based on TDDFTB theory, which accurately describes photophysical and photochemical phenomena and provides a theoretical simulation tool for predicting the properties of complex materials.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Multidisciplinary Sciences
Igor Gaidai, Dmitri Babikov, Alexander Teplukhin, Brian K. Kendrick, Susan M. Mniszewski, Yu Zhang, Sergei Tretiak, Pavel A. Dub
Summary: In this work, the authors demonstrate the practical prospect of using quantum annealers for simulating molecular dynamics. They develop a methodology called Quantum Differential Equations (QDE) to propagate classical trajectories for the vibration of the hydrogen molecule. The results obtained using the D-Wave 2000Q quantum annealer are consistent, quickly converging to the analytical reference solution. Combining the quantum annealer with classical post-processing yields the most accurate results and highest efficiency. The QDE framework developed here is general and can be applied to solve any system of first-order ordinary nonlinear differential equations using a quantum annealer.
SCIENTIFIC REPORTS
(2022)
Article
Chemistry, Physical
Hsinhan Tsai, Dibyajyoti Ghosh, Wyatt Panaccione, Li-Yun Su, Cheng-Hung Hou, Leeyih Wang, Lei Raymond Cao, Sergei Tretiak, Wanyi Nie
Summary: This research reveals a direct correlation between the voltage instability of perovskite-based solid-state radiation detectors and humidity levels. By adding a protective barrier layer on the perovskite, the voltage damage can be prevented and stability can be enhanced. The study provides a mechanistic understanding and a practical solution for addressing the voltage instability in solid-state radiation detectors.
ACS ENERGY LETTERS
(2022)
Review
Chemistry, Multidisciplinary
Nikita Fedik, Roman Zubatyuk, Maksim Kulichenko, Nicholas Lubbers, Justin S. Smith, Benjamin Nebgen, Richard Messerly, Ying Wai Li, Alexander Boldyrev, Kipton Barros, Olexandr Isayev, Sergei Tretiak
Summary: Machine learning is becoming the preferred method for modeling complex chemical processes and materials. It provides a surrogate model trained on reference data to establish a relationship between molecular structures and chemical properties. This Review highlights the developments in using machine learning to evaluate chemical properties and obtain simplified quantum-mechanical descriptions, as well as the challenges and future outlook in this field.
NATURE REVIEWS CHEMISTRY
(2022)
Article
Chemistry, Physical
Xiaoyan Wu, Baopi Liu, Thomas Frauenheim, Sergei Tretiak, ChiYung Yam, Yu Zhang
Summary: This study uses the Trajectory Surface Hopping (TSH) nonadiabatic molecular dynamics algorithm to simulate plasmon relaxation in Au-20 clusters, taking atomistic details into account. The simulation results show that the relaxation time is about 2.7 ps, and the lifetime of the phonon-induced plasmon dephasing process is approximately 10.4 fs.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Hsinhan Tsai, Dibyajyoti Ghosh, Eli Kinigstein, Bogdan Dryzhakov, Honora Driscoll, Magdalena Owczarek, Bin Hu, Xiaoyi Zhang, Sergei Tretiak, Wanyi Nie
Summary: The dynamic structure changes in metal halide perovskite lattice upon photoexcitation and its impact on carrier transport properties in Ruddlesden-Popper phase perovskite thin films are reported in this study. Time-resolved X-ray scattering technique reveals rapid lattice expansion and slow relaxation over 100 ns after photoexcitation. The expansion is attributed to lattice thermal fluctuations caused by photon energy deposition. High laser powers induce strong local structural disorder, increasing the charge dissociation activation energy and leading to localized transport.
Article
Mechanics
M. Serrano, K. Larkin, M. Ghommem, S. Tretiak, A. Abdelkefi
Summary: A multi-purpose energy harvesting microgyroscope system based on piezoelectric materials is proposed for small devices in remote areas. Numerical analysis shows that a system with a non-symmetric beam design is suitable for broadband energy harvesting. The nonlinear softening effects create a broadband frequency response with high voltage output, but careful selection of DC and AC voltages is necessary to avoid dynamic pull-in.
EUROPEAN JOURNAL OF MECHANICS A-SOLIDS
(2023)
Article
Mechanics
M. Serrano, K. Larkin, S. Tretiak, A. Abdelkefi
Summary: Most microelectromechanical systems (MEMS) are made from brittle materials that are prone to cracking. Understanding the potential influences cracks in MEMS is necessary for the longevity of these systems. This study developed an electromechanical model to capture the impacts of cracks on the performance of a damaged energy harvesting microgyroscope, and numerical methods were used to approximate the damage associated with distributed crack networks. The study revealed that cracks can significantly affect the static and dynamic behaviors of the microgyroscope energy harvester.
EUROPEAN JOURNAL OF MECHANICS A-SOLIDS
(2023)
Article
Chemistry, Physical
Hassiel Negrin-Yuvero, Victor M. Freixas, Dianelys Ondarse-Alvarez, Ana E. Ledesma, Sergei Tretiak, Sebastian Fernandez-Alberti
Summary: The photoexcitation, energy relaxation, and redistribution of a recently synthesized zigzag carbon nanobelt were studied using molecular dynamics simulations. The transition dipole moments and electronic transition density were found to gradually change during the internal conversion process. The electronic relaxation involved long-lived states with large energy gaps and changes in symmetry. These results provide insights into the excited-state properties of the zigzag nanobelt and can inspire the design of tailored nanobelts for specific nanoelectronic and photonic applications.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Chintam Hanmandlu, Rohan Paste, Hsinhan Tsai, Shyam Narayan Singh Yadav, Kuan-Wen Lai, Yen-Yu Wang, Chandra Shekar Gantepogu, Chen-Hung Hou, Jing-Jong Shyue, Yu-Jung Lu, Tushar Sanjay Jadhav, Jian-Ming Liao, Hsien-Hsin Chou, Hui Qi Wong, Chao-Sung Lai, Dibyajyoti Ghosh, Sergei Tretiak, Ta-Jen Yen, Hung-Ju Yen, Chih-Wei Chu
Summary: This study used a holistic interface strategy to enhance the efficiency and stability of perovskite solar cells by decreasing the number of interfacial defect states. The researchers utilized three-dimensional triphenylamine-based nanographene precursors to form a bridge between the perovskite film and the hole transport layer, resulting in improved performance characteristics.
Article
Chemistry, Physical
Hassiel Negrin-Yuvero, Victor M. Freixas, Dianelys Ondarse-Alvarez, Ana E. Ledesma, Sergei Tretiak, Sebastian Fernandez-Alberti
Summary: Progress in the synthesis of new carbon nanorings and nanobelts broadens the library of materials with unique structural and optical properties that can be attractive for further potential applications in host-guest chemistry, nanoelectronics, and photonics. In this study, we investigate the photoexcitation and subsequent energy relaxation and redistribution of a recently synthesized zigzag carbon nanobelt using nonadiabatic excited state molecular dynamics simulations. Our results reveal the excited-state dynamical properties of the zigzag-type nanobelt that differentiate this molecule from other nanobelts, providing insights for further designs tailored for specific nanoelectronic and photonic applications.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
