We have quantum chemically analyzed the structure and stability of archetypal chalcogen-bonded model complexes D Ch⋅⋅⋅A (Ch = O, S, Se, Te; D, A = F, Cl, Br) using relativistic density functional theory at ZORA-M06/QZ4P. Our purpose is twofold: (i) to compute accurate trends in chalcogen-bond strength based on a set of consistent data; and (ii) to rationalize these trends in terms of detailed analyses of the bonding mechanism based on quantitative Kohn-Sham molecular orbital (KS-MO) theory in combination with a canonical energy decomposition analysis (EDA). At odds with the commonly accepted view of chalcogen bonding as a predominantly electrostatic phenomenon, we find that chalcogen bonds, just as hydrogen and halogen bonds, have a significant covalent character stemming from strong HOMO-LUMO interactions. Besides providing significantly to the bond strength, these orbital interactions are also manifested by the structural distortions they induce as well as the associated charge transfer from A to D Ch.
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http://dx.doi.org/10.1002/open.202000323 | DOI Listing |
Commun Chem
January 2025
Institute of Chemical Sciences, Heriot-Watt University, Edinburgh, UK.
Various photoactive molecules contain motifs built on aza-aromatic heterocycles, although a detailed understanding of the excited state photophysics and photochemistry in such systems is not fully developed. To help address this issue, the non-adiabatic dynamics operating in azanaphthalenes under hexane solvation was studied following 267 nm excitation using ultrafast transient absorption spectroscopy. Specifically, the species quinoline, isoquinoline, quinazoline, quinoxaline, 1,6-naphthyridine, and 1,8-naphthyridine were investigated, providing a systematic variation in the relative positioning of nitrogen heteroatom centres within a bicyclic aromatic structure.
View Article and Find Full Text PDFJ Phys Chem B
January 2025
Department of Chemistry, Indian Institute of Technology (IIT) Indore, Indore, Madhya Pradesh 453552, India.
Artificially synthesized DNA holds significant promise in addressing fundamental biochemical questions and driving advancements in biotechnology, genetics, and DNA digital data storage. Rapid and precise electric identification of these artificial DNA strands is crucial for their effective application. Herein, we present a comprehensive investigation into the electric recognition of eight artificial synthesized DNA (DNA and DNA) nucleobases using quantum tunneling transport and machine learning (ML) techniques.
View Article and Find Full Text PDFJ Colloid Interface Sci
December 2024
Key Laboratory of New Energy Development and Energy Storage Technology of Handan, College of Materials Science and Engineering, Hebei University of Engineering, Handan 056038, People's Republic of China.
Herein, a novel composite solid-state polymer electrolytes (CSEs) was regulated by introducing CoNi-MOF (Metal-organic framework) @NiPc (Nickel phthalocyanine) nanofiller (CMN) into PEO (polyethylene oxide) matrix. In this novel system, the NiPc uniformly wrapped around the surface of MOF through hydrogen bond bridging, avoiding the agglomeration of the MOF particles. The chemisorption between Ni in NiPc and the O atoms in the bis(triffuoromethanesulfonyl)imide anion (TFSI) restricted the mobility of the anions within the CSEs, which improved the release of Li ions from the NiPcLi.
View Article and Find Full Text PDFAppl Biochem Biotechnol
January 2025
Centre for Applied Research, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences (SIMATS), Thandalam, Chennai, Tamil Nadu, 602105, India.
Nelumbo nucifera, an aquatic crop cultivated throughout Asian countries, belongs to the Nelumbonaceae family and has been widely used in traditional medicines with key pharmacological activities such as anti-viral, antipyretic, antioxidant, anti-steroid, anti-inflammatory, anti-arrhythmia, anti-obesity, and anti-aging properties. The present study aims to explore and assess the phytochemical composition, GC-MS profiling, antioxidant efficacy, and the major phytoconstituent phytol subjected to theoretical spectroscopic characterization using the DFT method. The phytochemical profiling of N.
View Article and Find Full Text PDFAlzheimers Dement
December 2024
Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, MA, USA.
Background: The unique lesion of chronic traumatic encephalopathy (CTE) is the perivascular deposition of hyperphosphorylated tau at the depth of the cortical sulci. The distribution and molecular composition of p-tau is distinct from Alzheimer's disease (AD), but differential diagnostic challenges remain. Understanding disease differences in regional density of p-tau will inform differential diagnosis and interpretation of in vivo biomarkers.
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