Article
Chemistry, Multidisciplinary
Taito Murakami, Maxim Avdeev, Riho Morikawa, James R. R. Hester, Masatomo Yashima
Summary: Proton conductors are promising materials for clean energy, but most available materials require chemical substitutions to show sufficient conductivity, leading to difficulties in sample preparation and chemical instability. Recently, proton conductors based on hexagonal perovskite-related oxides have been gaining attention for their high proton conductivity without the need for chemical substitutions. In this study, three types of oxides with different oxygen-deficient layers were used to investigate the roles of specific layers in proton conduction. It was found that undoped beta-Ba2ScAlO5 exhibited high proton conductivity, while structurally related oxides alpha-Ba2Sc0.83Al1.17O5 and BaAl2O4 showed lower conductivity. Ab initio molecular dynamics simulations revealed the migration of protons through the double-octahedral layer, with the h' layer acting as a proton reservoir. These findings provide a strategy for developing high-performance proton conductors.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Yuehui Li, Yantao Shi, Xuedan Song, Zhengyan Zhao, Naitian Zhang, Ce Hao
Summary: In this study, the state and dynamic equilibrium of glycolaldehyde in methanol solution were systematically investigated. It was found that glycolaldehyde hemiacetal (GAHA) is the dominant component in methanol solution, with more than 90% abundance. The study provides important insights into the analysis of sugars and related compounds in biochemical reactions.
NEW JOURNAL OF CHEMISTRY
(2021)
Article
Chemistry, Physical
Qiaozhuo Wu, Xiaoying Xie, Qingzhong Li, Steve Scheiner
Summary: When attached to a tetrazole, a TtR(3) group forms a TtMIDLINE HORIZONTAL ELLIPSISN tetrel bond with the Lewis base NCM. The SiMIDLINE HORIZONTAL ELLIPSISN TtB is strong, while the CMIDLINE HORIZONTAL ELLIPSISN TtBs are relatively weaker. The addition of a BH3 or BF3 molecule intensifies these bonds.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Multidisciplinary Sciences
Jeng-Yuan Tsai, Jinbo Pan, Hsin Lin, Arun Bansil, Qimin Yan
Summary: The study identifies suitable defect centers in two-dimensional transition metal dichalcogenides and assesses their potential as solid-state spin qubits through high-throughput simulations. The authors show that these atomically thin materials offer a new platform for scalable qubit fabrication and operation at room temperature. The presence of neutral antisite defects in the transition metal dichalcogenides is found to enable controllable spin qubits with a paramagnetic triplet ground state.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Applied
Jose P. Ceron-Carrasco, Natalia Sanchez, Denis Jacquemin
Summary: In this study, curcuminoid analogues were combined with cisplatin to design a series of prodrugs that can be photo-activated by visible light. The simulations revealed two novel complexes absorbing in the first phototherapeutic window (600-800 nm). The optimization of these structures for photoactivated chemotherapy is discussed.
Article
Chemistry, Physical
Saikat Mukherjee, Mario Barbatti
Summary: The problem of zero-point energy leakage in classical trajectory calculations can be prevented by using the LP-ZPE method, which pumps back leaked energy into corresponding vibrational modes.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2022)
Article
Chemistry, Multidisciplinary
Qian-Rui Huang, Ryunosuke Shishido, Chih-Kai Lin, Chen-Wei Tsai, Jake A. Tan, Asuka Fujii, Jer-Lai Kuo
Summary: The study analyzed the infrared spectra of a series of asymmetric proton-bound dimers with protonated trimethylamine as the proton donor, revealing a red shift in the N-H+ stretching mode frequency as the proton affinity of acceptors increases. Despite the expected pattern, the observed band showed a peculiar splitting of around 300 cm(-1) with intensity resembling a two-level system. Theoretical investigation attributed this band splitting to strong coupling between the proton stretching mode and overtone states of proton bending modes, known as Fermi resonance, providing a general theoretical model linking the strong coupling to a quasi-two-level system intrinsic to proton motions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Biotechnology & Applied Microbiology
Le Thanh Mai Pham, Kai Deng, Trent R. Northen, Steven W. Singer, Paul D. Adams, Blake A. Simmons, Kenneth L. Sale
Summary: This study investigates the effect of pH on the enzyme-catalyzed cleavage of beta-O-4 ' ether bonds and C-C bonds by lignin peroxidase isozyme H8. Results show that lowering pH can enhance the enzyme activity, reducing the energetic barriers for bond cleavage through protonation. It is suggested that engineering of lignin peroxidase isozyme H8 and other enzymes involved in lignin depolymerization should target stability at low pH.
BIOTECHNOLOGY FOR BIOFUELS
(2021)
Article
Nanoscience & Nanotechnology
B. Akdim, C. Woodward, S. Rao, E. Antillon
Summary: Recent studies have shown that chemically-complex solid-solution alloys produce equilibrium dislocations at high temperatures, leading to kinks and pinning points that significantly increase strength. Atomistic studies and chemical analysis can help understand the effects of different alloy compositions on dislocation formation.
SCRIPTA MATERIALIA
(2021)
Article
Chemistry, Physical
Leszek M. Malec, Mateusz Z. Brela, Katarzyna M. Stadnicka
Summary: This work investigates the dynamic character of hydrogen-bond networks in two three-component crystals comprising polycationic chains. X-ray diffraction measurements and molecular dynamics computations were used to study the hydrogen-bond systems in both crystals, revealing proton transfer phenomena occurring at 300 K.
Article
Chemistry, Multidisciplinary
Weixing Li, Denis S. Tikhonov, Melanie Schnell
Summary: Proton transfer via tunneling is a fundamental quantum-mechanical phenomenon, as demonstrated by rotational spectroscopy measurements on the complex of formic acid dimer with fluorobenzene. The presence of fluorobenzene does not quench the double proton transfer in the formic acid dimer, but instead decreases its tunneling splitting. Calculations suggest that fluorobenzene's weak binding does not affect the activation energy of proton transfer, but does slow down the proton transfer motion during the reaction.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Physical
Anmol Kumar, Poonam Pandey, Payal Chatterjee, Alexander D. Jr Jr MacKerell
Summary: The Drude polarizable force field captures electronic polarization effects and is useful for simulating biomolecules and other molecules. Deep neural network models can accurately predict molecular dipole moments and polarizabilities.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2022)
Article
Chemistry, Physical
Shichen Lin, Daoling Peng, Weitao Yang, Feng Long Gu, Zhenggang Lan
Summary: The dissociation of hydrogen atoms from formaldehyde in the lowest triplet state was studied using a high-dimensional machine-learning potential energy surface model. The use of a deep-learning neural network to represent the PES function allowed for accurate simulations and exploration of vibrational excitation effects on the dissociation dynamics. The results showed that specific vibrational excitations enhance the probability of hydrogen atom dissociation in the T-1 state.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Biochemistry & Molecular Biology
Greta Donati, Nadia Rega
Summary: Fluorescent proteins have multiple applications in technology and biotechnology, but understanding all the non-equilibrium photo-induced processes that govern their properties remains a challenge. Theoretical-computational approaches can offer insight into these processes and aid in understanding the reaction mechanisms.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Chemistry, Physical
Dongmei Zhang, Yong Lu, Jie Wang, Chu Gong, Xuesen Hou, Xinxing Zhang, Jun Chen
Summary: This study re-examines the synthesis method of the cyclohexanehexone molecule, confirming its structure and chemical bonding through mass spectrometry and theoretical calculations. It provides a benchmark understanding of the historically elusive C6O6.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)