Article
Chemistry, Physical
Ilya I. Marochkin, Vladimir V. Kuznetsov, Zhidong Li, Anatolii N. Rykov, Nina N. Makhova, Igor F. Shishkov
Summary: The molecular structure and properties of 1,2-diethyldiaziridine were studied experimentally and computationally, leading to the determination of structural parameters and standard enthalpy of formation for this compound. The results indicate a good agreement between experimental data and theoretical predictions.
JOURNAL OF MOLECULAR STRUCTURE
(2021)
Article
Chemistry, Physical
Scott A. Southern, Michael S. West, Maressa J. Z. Bradshaw, David L. Bryce
Summary: This study investigates the impact of tetrel bonds on C-13 and H-1 solid-state NMR spectroscopic responses, revealing that tetrel bonds can moderately increase the chemical shift of methyl(13)C atoms with a weak inverse correlation with bond length. Methyl proton chemical shifts are also influenced by tetrel bonds, although no strong correlations with structural features were observed based on experimental data. The research highlights the importance of understanding how tetrel bonds and weak CH···O hydrogen bonds can affect NMR responses in crystallography applications.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Physical
Alexey V. Eroshin, Tran Dinh Phien, Peter M. Weber, Sergey A. Shlykov
Summary: The conformational preferences of substituted, saturated cyclic ketones may differ from their oxygenless analogues. 1-Phenylpiperidin-4-one was found to exist in multiple forms with variations in the position and configuration of the aryl-substituent and piperidine cycle. Gas-phase electron diffraction and mass spectrometric experiments confirmed the contributions of co-existing species predicted by quantum chemical calculations, with the best fit observed using the B3LYP-D3/cc-pVTZ combination.
CHEMICAL PHYSICS LETTERS
(2022)
Article
Materials Science, Multidisciplinary
Yayoi Tanaka, Hisashi Sato, Osamu Eryu
Summary: In this study, a fixed abrasive wheel for solid phase chemical-mechanical polishing (SPCMP) was developed to successfully sharpen the cutting edge of cemented carbide (WC-Co) tools and remove latent flaws. SPCMP method can remove latent scratches from the surfaces of WC-Co materials, as well as reduce wear rate and extend the service life of the tools.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Chemistry, Physical
I. N. Kolesnikova, S. V. Kolesnikov, N. V. Lobanov, P. Yu. Sharanov, A. A. Larin, F. E. Teslenko, L. L. Fershtat, I. F. Shishkov
Summary: The equilibrium molecular structure of 3,4-dicyanofuroxan was determined for the first time using gas electron diffraction (GED) and quantum chemical (QC) calculations. The GED values were compared to QC computations at different levels of theory, revealing the sensitivity of the O1-N2 bond value to the QC method applied. The best fit to the experimental data was achieved with CCSD(T)/cc-pVTZ, while the DFT methods used in this study were found to be less accurate. Peculiar features of the 3,4-dicyanofuroxan molecular structure were revealed through NBO, AIM, and NCI analyses.
CHEMICAL PHYSICS LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Marco Marciani, Lara Benfatto
Summary: The study explores the transport in a multiband weakly disordered noninteracting crystal under a small electric field using the Boltzmann approach. A semi-analytical solution to the Boltzmann equation is provided to simplify the numerical computation, enabling the discussion of the interplay of symmetry and disorder for different impurity types. The research also considers the 2D isotropic Rashba metal as an example and discusses how different disorders may affect the exactness of the relaxation-time approximation, induce transport anisotropy, and identify the presence of spin-orbit coupling.
Article
Mathematics, Applied
Niels Benedikter, Marcello Porta, Benjamin Schlein, Robert Seiringer
Summary: Recently, the leading order of the correlation energy of a Fermi gas in a coupled mean-field and semiclassical scaling regime has been derived, under the assumption of an interaction potential with a small norm and with compact support in Fourier space. We generalize this result to large interaction potentials, requiring only | center dot | (V) over cap epsilon l(1)(Z(3)). Our proof is based on approximate, collective bosonization in three dimensions. Significant improvements compared to recent work include stronger bounds on non-bosonizable terms and more efficient control on the bosonization of the kinetic energy.
ARCHIVE FOR RATIONAL MECHANICS AND ANALYSIS
(2023)
Article
Chemistry, Physical
Christoph Foerster, Helena Osthues, Dominik Schwab, Nikos L. Doltsinis, Katja Heinze
Summary: In this study, the structural changes of chromium(III) cations under pressure and their effects on excited state energies were investigated using density functional theory with periodic boundary conditions and high-level CASSCF-NEVPT2 calculations. It was found that the differences in pressure sensitivity of the two spin-flip emission bands can be attributed to the different orbital occupation of the intraconfigurational excited states.
Article
Chemistry, Multidisciplinary
Shike Li, Yanming Zhu, Yang Wang, Jing Liu
Summary: The study quantitatively characterized the coal structure using various techniques, showing different distributions of aromatic structural units in coals of different ranks, and indicating that as disorder increases, the molecular structure of coal undergoes changes.
Article
Nanoscience & Nanotechnology
Itisha Dwivedi, Arup Sarkar, Gopalan Rajaraman, Chandramouli Subramaniam
Summary: The electric field at the sharp tips of carbon nanotubes can accelerate chemical reactions at solid-gas interfaces, enabling site-specific chemical modifications. The application of an electric field can activate gas molecules and enhance reaction efficiency. This has significant implications for nanomaterial modifications and the development of miniaturized gas analyzers.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Pharmacology & Pharmacy
Petr Buikin, Anna Vologzhanina, Roman Novikov, Pavel Dorovatovskii, Alexander Korlyukov
Summary: Abiraterone acetate is a commonly used therapeutic agent for prostate cancer, but its poor solubility limits its effectiveness. In this study, d-metal complexes with Abiraterone acetate were obtained to improve its solubility and investigate its interaction with heme. The results showed that Abiraterone acetate can form stable complexes with dications and act as a bridge ligand in reactions with silver(I) nitrate. The bonding energies between Abiraterone acetate and these cations were found to be higher than those between metal atoms and water molecules.
Article
Chemistry, Physical
Alexander Belyakov, Vitalii A. Losev, Anatolii N. Rykov, Igor F. Shishkov, Vladimir V. Kuznetsov, Artem Khakhalev, Aleksei B. Sheremetev
Summary: The equilibrium molecular structure of the first pernitroheterocycle, 3,4-dinitrofurazan, was calculated for the first time using gas-phase electron diffraction with coupled cluster calculations. The study revealed the peculiar characteristics of 3,4-dinitrofurazan and compared them to the parent molecule.
JOURNAL OF MOLECULAR STRUCTURE
(2022)
Article
Chemistry, Inorganic & Nuclear
Sofia N. Vorobyeva, Nikita A. Shekhovtsov, Iraida A. Baidina, Taisiya S. Sukhikh, Sergey Tkachev, Mark B. Bushuev, Anatoly Belyaev
Summary: Four rhodium(III) nitrate complexes were synthesized, with examples of soluble complexes having four and five coordinated nitrato ligands, as well as a hexaaquarhodium(III) nitrate complex. The thermodynamic stability constants and kinetics of ligand substitution were studied experimentally and computationally to provide insights into their practical applications in various fields.
Article
Chemistry, Multidisciplinary
Hiroki Hayashi, Satoshi Maeda, Tsuyoshi Mita
Summary: This article introduces the application of quantum chemical calculations in the development of synthetic methodologies. It can be used to analyze the reaction mechanisms of developed reactions and predict unknown reactions. The use of computational methods allows researchers to explore unknown reactions, catalysts, and synthetic routes more effectively before conducting time-consuming and costly experimental investigations.
Article
Chemistry, Multidisciplinary
Hiroki Hayashi, Satoshi Maeda, Tsuyoshi Mita
Summary: Quantum chemical calculations play a crucial role in the development of synthetic methodologies by analyzing reaction mechanisms and predicting unknown reactions. They drive the discovery of new methodologies through efficient computation, saving time and costs compared to experimental investigations, and enable the exploration of synthetic routes to complex molecules and catalyst design.
Article
Chemistry, Multidisciplinary
Henric Steffenfauseweh, Dennis Rottschaefer, Yury V. Vishnevskiy, Beate Neumann, Hans-Georg Stammler, Dariusz W. Szczepanik, Rajendra S. Ghadwal
Summary: A bordeaux-red solid compound based on an anionic dicarbene (ADC) with a central six-membered C4Sb2 ring is reported. The compound undergoes 2 e-oxidation to form a brick-red solid with unpaired electrons and lone pairs. The diradical character of the compound is calculated to be 36-39% according to different methods.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Lucas Wickemeyer, Israel Fernandez, Beate Neumann, Hans-Georg Stammler, Norbert W. Mitzel
Summary: The oxygen-bridged frustrated Lewis pairs (FLPs) underwent selective complexation with azobenzene under UV irradiation. The adduct of the second FLP was stable, while the adduct of the first FLP showed a [3,3]-rearrangement resembling ortho-benzidine. Similar rearrangements were observed with different para-substituted azobenzenes and di(2-naphthyl)diazene, but not with ortho-methylated azo compounds. The characterization of all adducts was done by multinuclear NMR spectroscopy and elemental analyses, and the rearrangement mechanism was explored using quantum-chemical calculations.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Lucas Wickemeyer, Pia C. Trapp, Niklas Aders, Beate Neumann, Hans-Georg Stammler, Norbert W. Mitzel
Summary: The oxygen-bridged geminal frustrated Lewis pairs tBu(2)P-O-AlBis(2) (1) and tBu(2)P-O-Si(C2F5)(3) (2) react with heterocumulenes, forming addition products. While both 1 and 2 form five-membered ring addition products with isocyanate and cyanate, only 1 forms stable adducts with CS2, isothiocyanate, and sulfinylaniline. The reaction of 1 with SO2 leads to partial cleavage of the P-O-Al and Al-C units, whereas the reaction of 2 with SO2 affords the 1,2-addition product. All adducts are characterized using NMR spectroscopy, X-ray crystallography, and CHN analyses.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Inorganic & Nuclear
Lucas Wickemeyer, Jan Schwabedissen, Pia C. Trapp, Beate Neumann, Hans-Georg Stammler, Norbert W. Mitzel
Summary: A series of ortho-phenylene-bridged phosphorus-silicon Lewis pairs were synthesized, and their interactions were investigated experimentally and theoretically. The results showed stabilizing interactions between the acidic and basic units, which were mediated by electronic interactions through the ring rather than direct acid-base interactions. Spectroscopic and theoretical investigations confirmed the absence of direct interactions between silicon and phosphorus.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Multidisciplinary
Arne Merschel, Yury V. Vishnevskiy, Beate Neumann, Hans-Georg Stammler, Rajendra S. Ghadwal
Summary: Cyclic organoalane compounds [(ADC(Ar))AlH2](2) based on anionic dicarbene (ADC) frameworks have been reported. These compounds are stable crystalline solids and soluble in organic solvents. They exhibit annulated tricyclic structures with a planar central C4Al2-core embedded between two peripheral 1,3-imidazole rings.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Inorganic & Nuclear
Niklas Aders, Jan-Hendrik Lamm, Katharina Wels, Sophie Bernhardt, Beate Neumann, Hans-Georg Stammler, Norbert W. Mitzel
Summary: In this study, highly rigid cyclic and bicyclic compounds containing silicon and tin were synthesized using di-lithiated diethynylbenzene derivatives. The known precursor compounds were efficiently synthesized in a two-step one-pot reaction, resulting in yields up to 45% by alternating addition of the lithiation reagent and starting material. A total of ten compounds were synthesized, with the molecular structure in the solid state elucidated for six novel compounds. Host-guest experiments were conducted to investigate the potential of complexation of small anions using selected molecules. All compounds were characterized using various analytical techniques.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2023)
Review
Chemistry, Multidisciplinary
Norbert W. Mitzel, Jan-Hendrik Lamm
Summary: This article discusses the structural changes of molecules in different phases and the effects of noncovalent interactions. Through experiments and calculations, several specific cases are presented to explore the mechanisms of noncovalent interactions in stabilizing molecular structures and influencing conformations. The article aims to provide readers with an understanding of the types and magnitudes of structural changes in free molecules compared to molecules embedded in crystals, as well as predictive concepts for distortions and variations.
ACCOUNTS OF CHEMICAL RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
J. Louis Beckmann, Jonas Krieft, Yury V. Vishnevskiy, Beate Neumann, Hans-Georg Stammler, Norbert W. Mitzel
Summary: A bidentate pnictogen bonding host-system based on 1,8-diethynylanthracene was synthesized and investigated for its ability to form complexes with Lewis acidic or anionic guests. The adduct formation behavior and bonding situation were studied using various methods, including NMR spectroscopy, X-ray diffraction, elemental analyses, and computational methods.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Vanina M. Cayon, Mauricio F. Erben, Rosana M. Romano, Hans-Georg Stammler, Norbert W. Mitzel, Mao Fa Ge, Carlos O. Della Vedova
Summary: This study explores the chemistry and properties of disulfide-containing species, focusing on a family of compounds with the formula CCl3SSR. Various characterization techniques, including spectroscopy and spectroscopy, were used to analyze these compounds. The findings provide new insights into their behavior and potential applications.
Article
Chemistry, Physical
Denis S. Tikhonov, Yury V. Vishnevskiy
Summary: In this work, we propose a generally applicable Wigner sampling method and introduce a new, simplified approach for modeling molecular properties with nuclear quantum effects and vibrational anharmonicity. Our test calculations on various molecular systems, including vibrationally averaged rotational constants, vibrational IR spectra, and photoelectron spectra, demonstrate the performance of the Wigner sampling method. The developed simplified Wigner sampling method shows particular advantages when applied to large and flexible molecules.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Yury V. V. Vishnevskiy, Arseniy A. A. Otlyotov, Jan-Hendrik Lamm, Hans-Georg Stammler, Georgiy V. V. Girichev, Norbert W. W. Mitzel
Summary: The molecular structure of acenaphthene was determined experimentally using gas electron diffraction intensities and rotational constants. High-level quantum-chemical calculations and X-ray diffraction experiments were used to refine the structure. Different schemes of data averaging and weighting were explored to obtain accurate structural parameters. The study also investigated the elongation of C-C bonds in acenaphthene and predicted the possibility of longer C-C bonds in derivatives.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Vanina M. Cayon, Mauricio F. Erben, Rosana M. Romano, Hans-Georg Stammler, Norbert W. Mitzel, Carlos O. Della Vedova
Summary: Phenyl and pentafluorophenyl trifluorothioacetate were successfully prepared by condensation reactions and characterized using various spectroscopy techniques. The crystal structures of both compounds were determined, and the conformational preferences were studied using FTIR spectroscopy. Quantum-chemical calculations were also performed to further analyze the structures and UV-Vis spectra. The findings confirmed the syn conformational transferability found in thioesters and esters, which has implications in biological processes.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Arne Merschel, Yury V. Vishnevskiy, Beate Neumann, Hans-Georg Stammler, Rajendra S. Ghadwal
Summary: An unprecedented ring-opening of mesoionic carbenes (iMICs) based on an 1,3-imidazole scaffold to yield N-ethynylformimidamide (eFIM) derivatives as crystalline solids. The eFIMs are thermally stable under an inert atmosphere and show moderate air stability. They are excellent surrogates of iMICs and readily undergo ring-closing click reactions with a variety of main-group as well as transition metal Lewis acids to form challenging iMIC-compounds in good to excellent yields.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
