Results 21 to 30 of about 40,114 (276)
Hydrogenated polycyclic aromatic hydrocarbons: isomerism and aromaticity
Physical Chemistry Chemical Physics, 2020 A simple model based on adjacency matrices is introduced to study the stability of hydrogenated polycyclic aromatic hydrocarbons. Aromaticity governs their relative stability having the most stable isomers the higher number of non-hydrogenated rings.
Paula Pla +3 more
openaire +3 more sources
Hyperconjugative aromaticity and protodeauration reactivity of polyaurated indoliums
Nature Communications, 2019 Hyperconjugative aromaticity combines the concepts of hyperconjugation and aromaticity and explains cyclopentadiene stability. Here, the authors demonstrate extended hyperconjugative aromaticity in a metallated indole ring, which shows extended electron ...
Kui Xiao, Yu Zhao, Jun Zhu, Liang Zhao
doaj +1 more source
From mass to structure: An aromaticity index for high-resolution mass data of natural organic matter [PDF]
, 2006 Recent progress in Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS) provided extensive molecular mass data for complex natural organic matter (NOM). Structural information can be deduced solely from the molecular masses for ions with
Benecke +16 more
core +1 more source
Molecules, 2018 With their versatile molecular topology and aromaticity, porphyrinoid systems combine remarkable chemistry with interesting photophysical properties and nonlinear optical properties.
Tatiana Woller +4 more
doaj +1 more source
The Silacyclobutene Ring: An Indicator of Triplet State Baird-Aromaticity
Inorganics, 2017 Baird’s rule tells that the electron counts for aromaticity and antiaromaticity in the first ππ* triplet and singlet excited states (T1 and S1) are opposite to those in the ground state (S0). Our hypothesis is that a silacyclobutene (SCB) ring fused with
Rabia Ayub +2 more
doaj +1 more source
Recent Advances in the Reactions of Cyclic Carbynes
Molecules, 2020 The acyclic organic alkynes and carbyne bonds exhibit linear shapes. Metallabenzynes and metallapentalynes are six- or five-membered metallacycles containing carbynes, whose carbine-carbon bond angles are less than 180°.
Qian Su +7 more
doaj +1 more source
Characterization of the Structure of Saudi Crude Asphaltenes by X-ray Diffraction [PDF]
, 1997 Structural characterization studies have been carried out on four commercial Saudi Arabian crude oils. The aromaticity and crystallite parameters of the asphaltenes were studied by X-ray diffraction methods and compared to the average structural ...
Ali, Mohammad F. +2 more
core +4 more sources
Journal of Molecular Structure, 2014 We report experimental and theoretical evidences for supramolecular aromaticity as a new concept to be widely used in researches about molecular crystals. CSD survey regarding frequently encountered resonance-assisted H-bonds (RAHBs) in formic acid, formamide, formimidamide, formic acid-formamide, and formamide-formimidamide dimers shows that ...
Karabiyik, Hande +2 more
openaire +3 more sources
Influence of production variables and starting material on charcoal stable isotopic and molecular characteristics [PDF]
, 2008 We present a systematic study on the effect of starting species, gas composition, temperature, particle size and duration of heating upon the molecular and stable isotope composition of high density (mangrove) and low density (pine) wood.
Alemany +76 more
core +1 more source
Química Nova, 2009 In this paper the evolution of the concept of aromaticity is discussed. It considers not only historical aspects of the aromaticity concept but also the different criteria (theoretical and experimental) that have appeared to explain the properties of the
Giovanni Finoto Caramori +1 more
doaj +1 more source