Article
Chemistry, Physical
Pablo Roseiro, Nadia Ben Amor, Vincent Robert
Summary: The spin states of a Co(II) oxoverdazyl compound are investigated in this study. The results show a mixture of low-spin and high-spin states, which is influenced by the structure of the coordination sphere. This finding has significant implications for molecular magnetism.
Article
Chemistry, Multidisciplinary
Markus R. P. Pielmeier, Tom Nilges
Summary: Phosphorene and SnIP are two-dimensional and one-dimensional semiconductors formed from black phosphorus and SnI2, synthesized through mineralization and short way transport with similar yet different preparation methods. Investigating the formation mechanisms of these two compounds is of crucial importance for energy conversion, storage, and catalysis applications.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Enrique M. Arpa, Ines Corral
Summary: Unconjugated pterins are widely present and have various enzymatic functions, potentially participating in singlet oxygen, amino acid, and nucleotide photosensitization. Under UV-A light excitation, some of these pterins degrade, leading to hydrogen peroxide production. This process, occurring in vivo, contributes to oxidative stress and melanocyte destruction in vitiligo. Our study provides mechanistic insights into the formation of transient triplet species that trigger Type I and Type II photosensitizing processes and degradation. Through calculations, we demonstrate that 6-biopterin degradation in vitiligo patients' skin produces 6-formylpterin and subsequently 6-carboxypterin. The changes in photosensitizing potential with pH are attributed to modulation of excited-state redox potentials.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Biochemistry & Molecular Biology
Michal F. Rode, Daniela Nedeltcheva-Antonova, Liudmil Antonov
Summary: This study investigates in depth the ground state proton transfer and isomerization properties of two tautomeric Schiff bases, as well as calculates the excited state energy profiles. The obtained results are discussed in light of existing experimental data.
Article
Chemistry, Multidisciplinary
Paul Schmid, Felipe Fantuzzi, Jonas Klopf, Niklas B. Schroeder, Rian D. Dewhurst, Holger Braunschweig, Volker Engel, Bernd Engels
Summary: This issue features the research work of Bernd Engels, Holger Braunschweig, Volker Engel and their coworkers at University of Wurzburg on bridged boron compounds, highlighting the fascinating relationships between their composition, geometrical structures, and electronic structures.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Materials Science, Multidisciplinary
Alexander V. Bakulin, Lora S. Chumakova, Boris M. Elfimov, Svetlana E. Kulkova
Summary: The mechanisms of Ti and Si self-diffusion in Ti5Si3 compound were studied using the projector augmented-wave method within density functional theory. Migration and activation energies for Ti and Si atoms were calculated for vacancy and interstitial mechanisms. It was found that the smallest migration energy for Ti atom occurred in the interstitial mechanism, while for Si atom, it was 0.08 eV lower in the own-sublattice mechanism than in the interstitial one. The concentration of initial point defects and the preferred defects were determined. The temperature-dependent self-diffusion coefficients were calculated along two crystallographic directions, revealing that Ti atom diffuses faster than Si atom. The influence of metals of IVB-VIIB groups on Ti migration energy was also estimated, showing that most impurities increase migration energy and reduce Ti diffusivity in Ti5Si3.
COMPUTATIONAL MATERIALS SCIENCE
(2023)
Article
Chemistry, Physical
Adam Rettig, Martin Head-Gordon, Srinivas Doddipatla, Zhenghai Yang, Ralf Kaiser
Summary: The gas-phase preparation of ethynylsilylene through single-collision conditions has been studied, showing a barrierless reaction pathway and the formation of a distinct intermediate. The system of dicarbon-silane serves as a benchmark to explore the consequence of a single collision, leading to the formation of a nonclassical silacarbene.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Chemistry, Physical
Juan J. J. Aucar, Alejandro F. F. Maldonado, Juan I. I. Melo
Summary: In this work, relativistic corrections to the electric field gradient (EFG) are presented, including spin-dependent corrections for the first time. The results show that these new corrections significantly improve the performance of the existing method and are in close agreement with calculations at the four-component Dirac-Hartree-Fock (4c-DHF) level. The accuracy of the EFG values obtained with this new method allows for the analysis of the electronic origin of relativistic effects using well-known nonrelativistic operators.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Zisheng Zhang, Tsugunosuke Masubuchi, Philippe Sautet, Scott L. Anderson, Anastassia N. Alexandrova
Summary: We studied the size-dependent activity and stability of supported Pt-1, Pt-4, Pt-7, and Pt-8 for electrocatalytic hydrogen evolution reaction and found that clusters have higher activity than polycrystalline Pt, along with size-dependent stability. DFT calculations were used to understand the size effects by studying the structural fluxionality under different potentials. Our research showed that the clusters can reshape under H coverage, leading to a diverse ensemble of states with varying stoichiometry, structure, and reactivity. Both experimental and theoretical results suggest that the electrocatalytic species are hydridic states of the clusters (2 H/Pt). An ensemble-based kinetic model reproduced the experimental activity trend and highlighted the role of metastable states. The stability trend was rationalized through chemical bonding analysis. Our joint study showcases the potential- and adsorbate-coverage-dependent fluxionality of subnano clusters of different sizes and provides a systematic modeling strategy to tackle the complexities.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Solana Di Pino, Yamila A. Peerez A. Sirkin, Uriel N. Morzan, Veronica M. Sanchez, Ali Hassanali, Damian A. Scherlis
Summary: Nanoconfinement effects on water dissociation and reactivity at interfaces, pores, or aerosols remain controversial. Using ab initio simulations, we demonstrate that water dissociation is conserved intact to unexpectedly small length-scales, down to aggregates of only a dozen molecules or pores of widths below 2 nm. This work provides a fundamental description of water dissociation at different scales with implications on reactivity at the air-liquid interface.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Di Yang, Chunyu Zhao, Ruqian Lian, Lin Yang, Yizhan Wang, Yu Gao, Xu Xiao, Yury Gogotsi, Xudong Wang, Gang Chen, Yingjin Wei
Summary: A method for achieving planar, dendrite-free Li metal growth on Ti3C2Tx MXene is reported, overcoming the barrier of irregular and nonplanar electrodeposition of Li. The prepared Li metal anode demonstrates stable cycling and high capacity retention, making it promising for application in Li metal batteries.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Chemistry, Physical
Jing Shang, Congxin Xia, Chun Tang, Chun Li, Yandong Ma, Yuantong Gu, Liangzhi Kou
Summary: The bending deformation of AgBiP2Se6 monolayers can manipulate the polarization direction and domain size, significantly improving the ferroelectric stability. This mechano-ferroelectric coupling represents a new mechanism for stabilization and polarization flip in 2D ferroelectrics, with potential applications in next-generation non-volatile storage devices.
NANOSCALE HORIZONS
(2021)
Article
Chemistry, Multidisciplinary
Andrei Gurinov, Benedikt Sieland, Andrey Kuzhelev, Hossam Elgabarty, Thomas D. Kuehne, Thomas Prisner, Jan Paradies, Marc Baldus, Konstantin L. Ivanov, Svetlana Pylaeva
Summary: A novel set of polarizing agents - mixed-valence compounds have been investigated through theoretical and experimental methods, showcasing their performance in high-field dynamic nuclear polarization (DNP) NMR experiments in the solid state. These compounds, with molecular mobility persisting even in solids, can be used to conduct Overhauser-DNP experiments in the solid state, providing favorable conditions for dynamic nuclear polarization formation at ultra-high magnetic fields.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Materials Science, Multidisciplinary
Michael Musi, Stefan Kardos, Lukas Hatzenbichler, David Holec, Andreas Stark, Melissa Allen, Volker Guther, Helmut Clemens, Petra Spoerk-Erdely
Summary: In recent years, Zr has emerged as a promising alloying element for intermetallic gamma-TiAl based alloys to improve their mechanical properties. This study focuses on the influence of Zr on the microstructure and thermodynamic phase equilibria in the ternary Ti-(42-46)Al-(2-4)Zr (at.%) system. The results show that alloying with Zr increases the amount of the gamma phase and enhances the hardness of the material. Additionally, the high Zr alloyed materials exhibit a decrease in solidus temperature. These findings are important for understanding and optimizing the performance of gamma-TiAl based alloys.
Article
Nanoscience & Nanotechnology
Fatima Akhtar, Jaroslaw Dabrowski, Rasuole Lukose, Christian Wenger, Mindaugas Lukosius
Summary: This study demonstrates the importance of uniform growth in the fabrication of graphene devices by reporting on the growth of large-scale, high-quality monolayer graphene on semiconducting 8-inch Ge(110)/Si wafers using chemical vapor deposition. The quality of graphene is indicated by small FWHM of the Raman 2D band, low intensity ratio of the Raman D and G bands, and homogeneous SEM images. Hall measurements confirm the high mobility and low sheet resistance of the graphene. The difference in growth mechanisms between Ge(001) and Ge(110) is attributed to their unique surface geometries and complex reconstructions.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Review
Biochemistry & Molecular Biology
Beatriz G. G. de la Torre, Fernando Albericio
Summary: While the world was battling with the COVID-19 Omicron wave at the end of 2021, except for China, most countries ended 2022 with COVID-19 being treated like the flu. As a result, the U.S. Food and Drug Administration (FDA) only authorized 37 new drugs this year, compared to an average of 52 in the previous four years. This marks the second lowest number of drug approvals in the last six years, even though it may change in the future. The decrease in FDA approvals mainly applies to small molecule drugs, while biologics and TIDES have remained relatively constant.
Article
Chemistry, Organic
Josep M. Anglada, Jordi Poater, Ibeirio de P. R. Moreira, Josep Maria Bofill
Summary: The effect of chemical substituents on the singlet-triplet energy gap in p-quinodimethane and Thiele's hydrocarbons has been investigated using high-level theoretical calculations. The nature of the substituents plays a crucial role in controlling the singlet-triplet energy gap, with steric effects being the most determinant for pQDM analogues. Electron-withdrawing groups in the central ring favor the quinoidal form, while electron-donating group substituents favor the aromatic-diradical form in Thiele-like compounds, with an excess of electron donation reducing the diradical character. The electronic spectrum of these compounds predicts intense bands in the visible region, with characteristic electronic transitions in the near-IR region in some cases.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Nestor Garcia-Romeral, Angel Morales-Garcia, Francesc Vines, Iberio de P. R. Moreira, Francesc Illas
Summary: The electronic ground state of Ti2C MXene was determined using density functional theory calculations, showing a magnetic ground state with antiferromagnetically coupled ferromagnetic layers. A spin model consistent with the nature of the chemical bond was presented, and the relevant magnetic coupling constants were extracted from energy differences using a mapping approach. The estimated Neel temperature is approximately 220 +/- 30 K, suggesting potential applications in spintronics and related fields.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Isaac Alcon, Jordi Ribas-Arino, Iberio de P. R. Moreira, Stefan T. Bromley
Summary: Two-dimensional conjugated polymers (2DCPs) are organic 2D materials composed of arrays of carbon sp(2) centers connected by pi-conjugated linkers, and they are gaining attention for their potential applications in device technologies. In this study, we use first-principles calculations to predict the electronic and magnetic properties of a new class of hexagonally connected neutral mixed-valence 2DCPs. We find that these materials exhibit emergent superexchange-mediated antiferromagnetic interactions, making them a highly promising platform for the realization of all-organic quantum materials.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Review
Biochemistry & Molecular Biology
Fatima Tuz Zahra, Aamer Saeed, Khansa Mumtaz, Fernando Albericio
Summary: The tropylium ion is a versatile non-benzenoid aromatic species that serves as a catalyst in numerous organic transformations. It outperforms transition-metal catalysts with its yield, moderate conditions, non-toxic byproducts, functional group tolerance, selectivity, and ease of handling. This review highlights the importance of the tropylium ion as an environmentally safe catalyst and summarizes its role in various organic reactions.
Article
Chemistry, Multidisciplinary
Sisa Chalan-Gualan, Ivan Ramos-Tomillero, Thibault Terencio, Lola De Lima, Daniela G. Navas-Leon, Margarita Suarez, Nelson Santiago Vispo, Fernando Albericio, Hortensia Rodriguez
Summary: Cysteine-based perfluoroaromatic compounds, such as hexafluorobenzene (HFB) and decafluorobiphenyl (DFBP), were synthesized and used as versatile cores to construct molecular systems with interesting properties. DFBP was found to be more effective than HFB for the monoalkylation of thiols. Antibody-perfluorinated conjugates were prepared using thiol through two different strategies, demonstrating that bioconjugation did not affect the macromolecular entity. Spectroscopic characterization and theoretical calculations were used to evaluate the molecular properties of the synthesized compounds. Molecular docking predicted that cysteine-based DFBP derivatives could be potential binders for topoisomerase II alpha and COX-2, suggesting their potential as anticancer agents and candidates for anti-inflammatory treatment.
Article
Infectious Diseases
Maria Veronica Humpola, Roque Spinelli, Melina Erben, Virginia Perdomo, Georgina Guadalupe Tonarelli, Fernando Albericio, Alvaro Sebastian Siano
Summary: In this study, analogs of two antimicrobial peptides, C10:0-A2 and TA4, were designed and synthesized, and non-proteinogenic amino acids were used to improve their therapeutic properties. The physicochemical properties and antimicrobial activity of these analogs were analyzed. The results showed that substitution with D- and N-methyl amino acids could enhance stability against enzymatic degradation and modulate the therapeutic properties of antimicrobial peptides and lipopeptides. The study provides insights into the design and optimization of antimicrobial peptides for improved stability and therapeutic efficacy. TA4(dK), C10:0-A2(6-NMeLys), and C10:0-A2(9-NMeLys) were identified as the most promising molecules for further studies.
Article
Chemistry, Multidisciplinary
K. P. Nandhini, Mahama Alhassan, Clinton G. L. Veale, Fernando Albericio, Beatriz G. de la Torre
Summary: The solid-phase synthesis of Met-containing peptides often leads to the formation of impurities, Met(O) and sulfonium salt, due to oxidation and S-alkylation reactions. These reactions occur during the final acidolytic cleavage step. In this study, two new cleavage solutions were developed to eliminate oxidation and reduce S-alkylation. The optimal mixture for Cys-containing peptides was TFA-anisole-TMSCl-Me2S-TIS with triphenyl phosphine, while TIS was not required for other peptides. Both cleavage solutions were effective for sensitive amino acids like Cys and Trp. The sulfonium salt was successfully reversed to free Met-containing peptide by heating with acetic acid.
Article
Biotechnology & Applied Microbiology
Fanny Guzman, Monica Arostica, Tanya Roman, Dina Beltran, Adriana Gauna, Fernando Albericio, Constanza Cardenas
Summary: Solid-Phase Peptide Synthesis (SPPS) is a widely used technique in research and production. Three different laboratory protocols have been implemented to fulfill diverse requirements. The results show that each protocol yields different purification and can be chosen based on specific needs.
ELECTRONIC JOURNAL OF BIOTECHNOLOGY
(2023)
Article
Chemistry, Physical
Josep Maria Bofill, Marco Severi, Wolfgang Quapp, Jordi Ribas-Arino, Iberio de P. R. Moreira, Guillermo Albareda
Summary: The study of using oriented external electric fields (OEEFs) to control chemical reactivity and predicting the optimal OEEF for a reaction has gained significant attention. This paper presents a model based on catastrophe and optimum control theories to find the optimal OEEF for a given reaction valley in the potential energy surface (PES). The model, called the polarizable molecular electric dipole (PMED) model, constructs the effective PES by adding a term accounting for the interaction of OEEF with the molecular system. The proposed model successfully predicts the optimal OEEF for two different reactions.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Biochemistry & Molecular Biology
Sinenhlanhla N. Mthembu, Amit Chakraborty, Ralph Schonleber, Fernando Albericio, Beatriz G. de la Torre
Summary: Morpholine, scoring 7.5 in greenness and not being regulated, is a promising candidate for Fmoc removal in solid-phase peptide synthesis (SPPS). Morpholine in dimethylformamide (DMF) (50%-60%) effectively removes Fmoc in SPPS, reduces diketopiperazine formation, and nearly eliminates aspartimide formation. Somatostatin has been successfully synthesized using 50% morpholine in DMF with the same purity as when using 20% piperidine-DMF, serving as proof of concept.
JOURNAL OF PEPTIDE SCIENCE
(2023)
Review
Biochemistry & Molecular Biology
Umair Rauf, Ghulam Shabir, Saba Bukhari, Fernando Albericio, Aamer Saeed
Summary: This paper summarizes the recent advancements in the synthesis and applications of ferrocene derivatives reported from 2016 to date. It focuses on the synthesis of diverse classes of organic compounds with ferrocene scaffolds and the development of applications of ferrocene-based organometallic compounds, particularly in the fields of biology, medicine, bio-sensing, chemosensing, asymmetric catalysis, materials, and industry.
Review
Chemistry, Multidisciplinary
Jessica T. Mhlongo, Ayman Y. Waddad, Fernando Albericio, Beatriz G. de la Torre
Summary: Antimicrobial peptides (AMPs) are promising candidates for combating multidrug resistance due to their heterogenous structures and broad-spectrum action. The combined use of AMPs with other antimicrobial agents provides a new arsenal of drugs with synergistic action, inhibiting the development of drug resistance. This review discusses various synergies of AMPs with antimicrobials and miscellaneous agents, providing guidance for improved clinical outcomes.
Article
Chemistry, Physical
Nestor Garcia-Romeral, Angel Morales-Garcia, Francesc Vines, Iberio de P. R. Moreira, Francesc Illas
Summary: The magnetic properties of Ti2C, Ti3C2, and Ti4C3 MXenes were studied using density functional theory. It was found that all MXenes exhibit magnetic behavior with antiferromagnetic coupling between the outer Ti layers. A spin model was proposed based on the analysis of the chemical bond, with diamagnetic Ti2+ ions in the inner layers and paramagnetic Ti+ centers on the surface. The magnetic coupling constants were found to depend on the functional used, with the nearest neighbor intralayer coupling always being ferromagnetic.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Nestor Garcia-Romeral, Angel Morales-Garcia, Francesc Vines, Iberio de P. R. Moreira, Francesc Illas
Summary: A systematic computational study was conducted to investigate the electronic ground state nature and properties of M2C MXenes. The results revealed diverse conductivity and spin configurations for different MXenes, providing valuable insights for understanding and designing MXene materials.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
