Structural Characterization of Sulfur-Containing Water Clusters Using a Density-Functional Based Tight-Binding Approach

2016 ◽  
Vol 120 (45) ◽  
pp. 9089-9100 ◽  
Author(s):  
Kseniia A. Korchagina ◽  
Aude Simon ◽  
Mathias Rapacioli ◽  
Fernand Spiegelman ◽  
Jérôme Cuny
Keyword(s):  
Structural Characterization ◽  
Density Functional ◽  
Water Clusters ◽  
Tight Binding ◽  
Sulfur Containing

Structural characterization of sulfur-containing aromatic compounds in heavy oils by FT-ICR mass spectrometry with a narrow isolation window

Fuel ◽  
2019 ◽  
Vol 240 ◽  
pp. 40-48 ◽  
Author(s):  
Ling Liu ◽  
Chunxia Song ◽  
Songbai Tian ◽  
Qundan Zhang ◽  
Xinheng Cai ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Structural Characterization ◽  
Aromatic Compounds ◽  
Heavy Oils ◽  
Sulfur Containing ◽  
Ft Icr

Design and structural characterization of the all-metal aromatic sandwich species [Bi3Au3Bi3]3−: insight from density functional theory

2017 ◽  
Vol 41 (6) ◽  
pp. 2321-2327 ◽  
Author(s):  
Li-Hong Tang ◽  
Ting-Ting Zhu ◽  
Ping Ning ◽  
Kai Li ◽  
Shuang-You Bao ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Structural Characterization ◽  
Density Functional ◽  
Functional Theory ◽  
Aromatic Structure

The [Bi3Au3Bi3]3− species, with hollow features, has a unique all-metal sandwich aromatic structure.

scholarly journals Estudo do tautomerismo ceto-enólico da 7-epi-clusianona através de cálculos teóricos de deslocamentos químicos de RMN

2020 ◽  
Author(s):  
Ana Carolina Ferreira de Albuquerque ◽  
José Walkimar de Mesquita Carneiro ◽  
Fernando Martins dos Santos Junior
Keyword(s):  
Natural Products ◽  
Structural Characterization ◽  
Density Functional ◽  
Theoretical Calculations ◽  
Chemical Shifts ◽  
Coupling Constants ◽  
Spectroscopic Techniques ◽  
Chemical Structures ◽  
Nmr Parameters

The properties of natural products, including their biological and pharmacological activities, are directly correlated with their chemical structures. Thus, a correct structural characterization of these compounds is a crucial step to the understanding of their biological activities. However, despite the recent advances in spectroscopic techniques, structural studies of natural products can be challenging. This way, theoretical calculations of Nuclear Magnetic Resonance (NMR) parameters (such as chemical shifts and coupling constants) have proven to be a powerful and low-cost tool for the aid to experimental techniques traditionally used for the structural characterization of natural products. One of the several applications of quantum-mechanical calculations of NMR parameters is the study of tautomerism. Since chemical shifts are sensitive to the tautomeric equilibrium, this technique can provide crucial informations. In this work, it was applied a protocol for theoretical calculations of ¹³C chemical shifts in order to study the tautomerism of the natural product 7-epi-clusianone, isolated from Rheedia gardneriana. This protocol consists in a Monte Carlo conformational search, followed by geometry optimization and shielding tensors calculations, both using a density functional level of theory. After comparison of theoretical and experimental data, it was possible to confirm the two tautomers present in equilibrium in the experimental solution. Furthermore, this study highlights how this theoretical protocol can be an effective method in identifying the preferred tautomeric form in solution.

scholarly journals Hydrosilyation of CO2 using a silatrane hydride: structural characterization of a silyl formate compound

2021 ◽  
Vol 99 (2) ◽  
pp. 259-267
Author(s):  
Serge Ruccolo ◽  
Erika Amemiya ◽  
Daniel G. Shlian ◽  
Gerard Parkin
Keyword(s):  
Molecular Structure ◽  
Density Functional Theory ◽  
Oxygen Atom ◽  
Structural Characterization ◽  
Density Functional ◽  
Density Functional Theory Calculations ◽  
X Ray Diffraction ◽  
Functional Theory ◽  
X Ray

The silatrane hydride compound, [N(CH2CH2O)3]SiH, reacts with CO2 in the presence of the [tris(2-pyridylthio)methyl]zinc hydride complex, [Tptm]ZnH, to afford the silyl formate and methoxide derivatives, [N(CH2CH2O)3]SiO2CH and [N(CH2CH2O)3]SiOCH3. The molecular structure of [N(CH2CH2O)3]SiO2CH has been determined by X-ray diffraction, thereby demonstrating that the formate ligand adopts a distal conformation in which the uncoordinated oxygen atom resides with a trans-like disposition relative to silicon. Density functional theory calculations indicate that the atrane motif of [N(CH2CH2O)3]SiO2CH is flexible, such that the energy of the molecule changes relatively little as the Si···N distance varies over the range 2.0–3.0 Å.

Sign in / Sign up

Export Citation Format

Share Document