Article
Materials Science, Multidisciplinary
Xiaowei Liang, Aitor Bergara, Xudong Wei, Xiaoxu Song, Linyan Wang, Rongxin Sun, Hanyu Liu, Russell J. Hemley, Lin Wang, Guoying Gao, Yongjun Tian
Summary: The study explores crystal structures and superconductivity in the La-B-H system under pressure using particle-swarm intelligence structure-searches methods and first-principles calculations. The research predicts that LaBH7 and LaBH8 can become dynamically stable and exhibit superconductivity at lower pressures. These results provide guidance for future experiments targeting hydride superconductors with lower synthesis pressures and higher T-c.
Article
Physics, Multidisciplinary
Junxiang Xiao, Jingwei Wen, Shijie Wei, Guilu Long
Summary: This article presents an adaptive framework that utilizes SWAP test, parameterized quantum circuits, and layerwise learning strategy to reconstruct unknown quantum states with high fidelity. Numerical simulations and experiments demonstrate the practical performance and applicability of the framework on quantum systems of different scales.
FRONTIERS OF PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Ravindranadh Bobbili, B. Ramakrishna
Summary: Predicting phases of high entropy alloys (HEAs) is a complex task depending on various parameters. Statistical models, including XGboost, random forest, adaboost, decision tree, logistic regression, support vector machine (SVM), and k-nearest neighbors (KNN), were adopted and XGboost algorithm showed the highest accuracy (90%). Machine learning methods accurately predicted phases and identified significant variables consistent with experimental results. It is recommended to use machine learning approaches widely to accelerate HEA research.
MATERIALS TODAY COMMUNICATIONS
(2023)
Article
Engineering, Aerospace
Miroslav Spodniak, Michal Hovanec, Peter Korba
Summary: This paper proposes a method based on artificial neural networks to predict the mechanical properties of the turbine section in jet engines. By measuring temperature, pressure, and rpm, the artificial neural network is trained using finite element analysis results to accurately predict mechanical stress. This method significantly reduces solving time compared to traditional finite element methods.
Article
Chemistry, Physical
Jincheng Qin, Zhifu Liu, Mingsheng Ma, Yongxiang Li
Summary: In this study, we optimized and extended Shannon's influential alpha(D) database for microwave frequencies using a four-stage multiple linear regression and support vector machine model. The optimized and extended databases achieved higher accuracy and increased the amount of data from 60 to over 900 compared to the conventional database. Additionally, we analyzed the relationships between alpha(D) and ion characteristics, including ionic radius, atomic number, valence state, and coordination number.
NPJ COMPUTATIONAL MATERIALS
(2023)
Article
Biochemical Research Methods
Lewis Moffat, David T. Jones
Summary: Using a bioinformatics approach to semi-supervised machine learning, the PASS framework was developed to accurately model single protein sequences, achieving unprecedented results in secondary structure prediction.
Article
Chemistry, Multidisciplinary
Mateusz A. Domanski, Karol Kraszewski, Piotr Paluch, Piotr A. Gunka
Summary: This study reports the synthesis and crystal structure determination of two new arsenic(III)-oxide intercalates with potassium chloride, as well as the redetermination of an anhydrous intercalate. New synthesis methods and thermal stability evaluation were described, and similarities in energetic factors between different compounds were revealed through interlayer interaction energy calculations.
CRYSTAL GROWTH & DESIGN
(2021)
Article
Chemistry, Organic
Patrycja Paciorek, Janusz Szklarzewicz, Bartosz Trzewik, Dariusz Ciez, Wojciech Nitek, Maciej Hodorowicz, Anna Jurowska
Summary: This study presents a simple and fast method for synthesizing pentasubstituted derivatives of pyrrole with high product quality that does not require purification, and can tolerate various substituents.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Nikita Rybin, Ilya Chepkasov, Dmitry Y. Novoselov, Vladimir I. Anisimov, Artem R. Oganov
Summary: This study investigates the stable phases of silver fluorides under high pressures using a first-principles variable-composition evolutionary algorithm. The obtained pressure-composition phase diagram differs from previous theoretical results and reveals previously unknown phases. The electronic correlation effects in the Ag-F system are also discussed in detail.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Review
Chemistry, Applied
David H. Bowskill, Isaac J. Sugden, Stefanos Konstantinopoulos, Claire S. Adjiman, Constantinos C. Pantelides
Summary: Crystal structure prediction is an important theoretical problem that has seen significant progress over the past 20 years. Current research efforts are focused on improving the reliability and widening applicability of these methodologies.
ANNUAL REVIEW OF CHEMICAL AND BIOMOLECULAR ENGINEERING, VOL 12, 2021
(2021)
Article
Chemistry, Physical
Edoardo Fertitta, Sujit Das, Debalina Banerjee, Farbod Ebrahimi, Clement Barraud, Kai Du, He Tian, Chris J. Pickard, Cedric Weber, Ramamoorthy Ramesh, Peter Littlewood, David Dubbink
Summary: The study focuses on the characterization of double perovskite oxides La2TiFeO6 and La2VCuO6, exploring B-site disorder and partial charge transfer between B-site ions. Utilizing random structure sampling method, multiple phases competing due to their configurational entropy were identified. Evaluation of information encapsulated in potential energy landscape via structure sampling optimized the metric for competition of different phases.
NPJ COMPUTATIONAL MATERIALS
(2021)
Review
Chemistry, Medicinal
Hikaru Kato
Summary: Natural products exhibit structural diversity, and computational chemistry can be used to determine their chemical structures, which is important in drug discovery research.
JOURNAL OF NATURAL MEDICINES
(2022)
Article
Engineering, Mechanical
H. M. Phan
Summary: The research indicates that decoupled methods are no longer sufficient for flutter predictions in the turbomachinery industry, leading to a shift towards fully-coupled methods. A spatial-temporal analysis approach based on the Hilbert transform is proposed to effectively elucidate the associated vibration mechanisms.
JOURNAL OF FLUIDS AND STRUCTURES
(2021)
Article
Physics, Applied
Victor T. Barone, Blair R. Tuttle, Sanjay V. Khare
Summary: Silver iodo-bismuthates, particularly AgBiI4, have potential for optoelectronic and other applications. This study uses high-throughput density functional and machine learning methods to determine the physically relevant unit cell configurations and calculate fundamental properties of the bulk material. The results are consistent with previous theory and experiment, and new predictions for bulk modulus and temperature-dependent conductivity masses are reported.
JOURNAL OF APPLIED PHYSICS
(2022)
Review
Chemistry, Multidisciplinary
Marley L. Samways, Richard D. Taylor, Hannah E. Bruce Macdonald, Jonathan W. Essex
Summary: The review highlights the fundamental importance of water molecules at drug-protein interfaces and discusses the challenges and advantages of experimental and computational methods to analyze their role in drug binding. It provides a critical analysis of experimental data used to validate computational methods and suggests directions for future research to address the fundamental difficulties of each method.
CHEMICAL SOCIETY REVIEWS
(2021)
Article
Engineering, Electrical & Electronic
Sara J. Dampf, Timothy M. Korter
JOURNAL OF INFRARED MILLIMETER AND TERAHERTZ WAVES
(2020)
Article
Chemistry, Multidisciplinary
Karlis Berzins, Joshua J. Sutton, Sara J. Fraser-Miller, Thomas Rades, Timothy M. Korter, Keith C. Gordon
CRYSTAL GROWTH & DESIGN
(2020)
Article
Chemistry, Physical
Alex Davie, Farah Vandrevala, Sara Dampf, Yanting Deng, Deepu K. George, Eric D. Sylvester, Timothy Korter, Erik Einarsson, Jason B. Benedict, Andrea G. Markelz
Summary: THz TDS is used to measure the melting kinetics of fructose molecular crystals, indicating phonon frequency changes and melting behavior. The kinetics follow a 3D growth model, with multiple H-bonds needing to break collectively for the transition.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Multidisciplinary
Margaret P. Davis, Timothy M. Korter
Summary: This study experimentally and computationally investigated the cocrystallization of urea and thiourea with glutaric acid and tartaric acid. The research found that the cocrystals of urea and thiourea with glutaric acid, as well as urea with DL-tartaric acid, are favorable for formation both experimentally and computationally.
CRYSTAL GROWTH & DESIGN
(2022)
Article
Medicine, Research & Experimental
Qi Li, Andrew D. Bond, Timothy M. Korter, J. Axel Zeitler
Summary: Terahertz time-domain spectroscopy was used to investigate two polymorphs of aspirin and confirmed their similar crystal structures and spectral features. Unique vibrational modes were identified for each polymorph, allowing for their discrimination. It was also found that form II had a greater degree of structural disorder and was expected to be more stable at higher temperatures.
MOLECULAR PHARMACEUTICS
(2022)
Article
Chemistry, Multidisciplinary
Alyssa Spear, Robson L. Schuarca, Jesse Q. Bond, Timothy M. Korter, Jon Zubieta, Robert P. Doyle
Summary: A new efficient catalyst that can absorb visible light for photocatalytic conversion of CO2 has been developed. By combining with a specific sacrificial donor, it can selectively produce formic acid with high turnover and turnover frequency.
Article
Chemistry, Multidisciplinary
Peter J. G. Remoto, Karlis Berzins, Sara J. Fraser-Miller, Timothy M. Korter, Thomas Rades, Jukka Rantanen, Keith C. Gordon
Summary: The dehydration of nitrofurantoin monohydrate II was studied using Raman spectroscopy at different isothermal conditions. Clear and subtle differences in the Raman spectra were observed for solid-state transformations. Multivariate curve resolution and theoretical modeling were used to analyze the solid-state forms and their relative abundances. Mid-frequency Raman spectroscopy detected the onset of the dehydration process earlier than low-frequency Raman spectroscopy.
CRYSTAL GROWTH & DESIGN
(2022)
Article
Chemistry, Physical
Mizuki Mohara, Margaret P. Davis, Timothy M. Korter, Kei Shimura, Touya Ono, Kenji Aiko
Summary: Understanding the solid-state transitions of active pharmaceutical ingredients (APIs) is crucial for quality control and bioavailability. Terahertz spectroscopy is a powerful tool for investigating the crystal structures of APIs. The study found that the ezetimibe monohydrate (EZT-MH) crystal has greater anharmonic character and is more stable than pure ezetimibe (EZT) and water. Additionally, the presence of excipients in the formulation tablets slows down the hydration process of the API.
JOURNAL OF PHYSICAL CHEMISTRY A
(2022)
Article
Medicine, Research & Experimental
Margaret P. Davis, Timothy M. Korter
Summary: Crystal polymorphism is a common phenomenon in pharmaceutical solids and can significantly affect the formulation of drug therapeutics. Low-frequency vibrational spectroscopy is a sensitive method to detect polymorphic content. In this study, the crystalline ribavirin, a widely applicable antiviral, was studied using terahertz time-domain spectroscopy and low-frequency Raman spectroscopy. The results showed that Form II of ribavirin is more stable at all temperatures due to a stronger cohesive energy, but Form I has a significantly lower conformational energy. This study provides important insights into the thermodynamic relationship of crystals.
MOLECULAR PHARMACEUTICS
(2022)
Article
Humanities, Multidisciplinary
Mary N. Boyden, Courtney K. Hicks, Timothy M. Korter
Summary: Crystopal is a mechanically strong and highly decorative plastic with a unique translucent and crackled appearance. Raman spectroscopy was used to determine the polymer composition of Crystopal artifacts, which were found to be composed of an unsaturated polyester crosslinked with styrene. This discovery adds Crystopal to the polymer database and provides a pathway for identifying and preserving objects made from this unique plastic.
Article
Chemistry, Multidisciplinary
Joshua Kirkham, Timothy M. Korter, Karlis Berzins, Cushla M. McGoverin, Keith C. Gordon, Sara J. Fraser-Miller
Summary: Low-frequency Raman spectroscopy and solid-state density functional theory were used to characterize variably substituted hydroxyapatites with Sr2+, F-, and CO3 (2-) as the substituting species in the crystalline and amorphous forms. The study demonstrated clear differences between amorphous and crystalline forms and systematic changes in the crystalline spectra with the level of substitution. A new crystallinity index (CI) based on low-frequency Raman intensities was proposed and showed better correlation with the XRPD-based CI compared to previous methods.
CRYSTAL GROWTH & DESIGN
(2023)
Article
Medicine, Research & Experimental
ShiZhe Shao, Michael W. Stocker, Salvatore Zarrella, Timothy M. Korter, Abhishek Singh, Anne Marie Healy
Summary: The aim of this study was to investigate the effect of different polymers on the dissociation of cocrystals prepared by co-spray-drying API, coformer, and polymer. It was found that the inclusion of certain polymers, such as PVP and PVPVA, in solid dispersions with the cocrystal DPCC effectively improved its physical stability and prevented dissociation in a high-humidity environment. This improvement is attributed to the efficient mixing between the polymer and cocrystal at the molecular level. The results suggest that polymer-based solid dispersions have the potential to enhance the stability of cocrystals.
MOLECULAR PHARMACEUTICS
(2023)
Proceedings Paper
Engineering, Electrical & Electronic
Margaret P. Davis, Timothy M. Korter
Summary: Amoxicillin and ampicillin, large and flexible antibiotic molecules, are commonly administered in their solid trihydrate forms. This study investigates the hydration of these pharmaceuticals using terahertz and low-frequency Raman vibrational spectroscopies, providing insights into the potential energy surfaces governing the large-amplitude motions of the co-crystalized waters. Experiment results combined with solid-state density functional theory simulations allow for an in-depth exploration of the vibrational modes and structures of the crystalline solids.
2021 46TH INTERNATIONAL CONFERENCE ON INFRARED, MILLIMETER AND TERAHERTZ WAVES (IRMMW-THZ)
(2021)
Article
Chemistry, Inorganic & Nuclear
Derek R. Case, Alyssa Spear, Adam F. Henwood, Max Nanao, Sara Dampf, Timothy M. Korter, Thorfinnur Gunnlaugsson, Jon Zubieta, Robert P. Doyle
Summary: A rhenium(i) naphthalimide complex was synthesized, characterized and evaluated as a photocatalyst for CO2 reduction, showing promising activity in the presence of triethylamine as a sacrificial electron donor. The compound was thoroughly characterized using various techniques, and its role in catalyzing the reduction of CO2 to formate was confirmed through experiments.
DALTON TRANSACTIONS
(2021)
Proceedings Paper
Engineering, Electrical & Electronic
Sara J. Dampf, Timothy M. Korter
2020 45TH INTERNATIONAL CONFERENCE ON INFRARED, MILLIMETER, AND TERAHERTZ WAVES (IRMMW-THZ)
(2020)