Effects of molecular structure on the stability of insoluble monolayers

1992 ◽  
Vol 65 (1) ◽  
pp. 29-42 ◽  
Author(s):  
R. Aveyard ◽  
B.P. Binks ◽  
N. Carr ◽  
A.W. Cross ◽  
G.W. Gray ◽  
...  
Keyword(s):  
Molecular Structure ◽  
The Stability

scholarly journals Synthesis of Bis(Carboranyl)amides 1,1′-μ-(CH2NH(O)C(CH2)n-1,2-C2B10H11)2 (n = 0, 1) and Attempt of Synthesis of Gadolinium Bis(Dicarbollide)

Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1321
Author(s):  
Yasunobu Asawa ◽  
Aleksandra V. Arsent’eva ◽  
Sergey A. Anufriev ◽  
Alexei A. Anisimov ◽  
Kyrill Yu. Suponitsky ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Single Crystal ◽  
Quantum Chemical Calculations ◽  
Quantum Chemical ◽  
X Ray Diffraction ◽  
Stable Conformation ◽  
Acyl Chlorides ◽  
X Ray ◽  
Cesium Fluoride ◽  
The Stability

Bis(carboranyl)amides 1,1′-μ-(CH2NH(O)C(CH2)n-1,2-C2B10H11)2 (n = 0, 1) were prepared by the reactions of the corresponding carboranyl acyl chlorides with ethylenediamine. Crystal molecular structure of 1,1′-μ-(CH2NH(O)C-1,2-C2B10H11)2 was determined by single crystal X-ray diffraction. Treatment of bis(carboranyl)amides 1,1′-μ-(CH2NH(O)C(CH2)n-1,2-C2B10H11)2 with ammonium or cesium fluoride results in partial deboronation of the ortho-carborane cages to the nido-carborane ones with formation of [7,7′(8′)-μ-(CH2NH(O)C(CH2)n-7,8-C2B9H11)2]2−. The attempted reaction of [7,7′(8′)-μ-(CH2NH(O)CCH2-7,8-C2B9H11)2]2− with GdCl3 in 1,2-dimethoxy- ethane did not give the expected metallacarborane. The stability of different conformations of Gd-containing metallacarboranes has been estimated by quantum-chemical calculations using [3,3-μ-DME-3,3′-Gd(1,2-C2B9H11)2]− as a model. It was found that in the most stable conformation the CH groups of the dicarbollide ligands are in anti,anti-orientation with respect to the DME ligand, while any rotation of the dicarbollide ligand reduces the stability of the system. This makes it possible to rationalize the design of carborane ligands for the synthesis of gadolinium metallacarboranes on their base.

Theoretical Study on Thermal Hazardous Properties of C18H10O11 and C18H18O7 Organic Peroxides

2013 ◽  
Vol 787 ◽  
pp. 301-305
Author(s):  
Yun Bo He ◽  
Wei Wang ◽  
Shi Xiong Wang ◽  
Xiang Jun Yang ◽  
Hong Guo
Keyword(s):  
Molecular Structure ◽  
Thermal Decomposition ◽  
Quantum Chemistry ◽  
Organic Compounds ◽  
Theoretical Study ◽  
Organic Peroxides ◽  
Quantum Chemistry Calculation ◽  
The Past ◽  
Chemistry Calculation ◽  
The Stability

The thermal decomposition of organic peroxides are widely used as coagulant for organic compounds, however, its thermal hazardous characteristics have already caused serious accidents in chemical industries, which limited its application in much more strict conditions. Organic peroxides of C18H10O11 and C18H18O7 are two new candidates fitted for industrial explosive. However, as we best known there is little reports available on the geometry structure in the past decades. In this work, by means of quantum chemistry calculation, the relation of safety with molecular structure of C18H10O11 and C18H18O7 are discussed. The molecules with more activity O and the activity part more dispersedly exhibit higher stable, and the configuration has good safety. All the energy of molecule b is higher than that of molecule a. The stability of different configurations are 6a>7a>8a>9a>5a>1a>4a>3a=2a and 1b>7b>5b>6b>4b>2b>3b>8b, respectively, suggesting the structures of 6a,3a,2a,1b,8b exhibit high safety.

Effects of surfactant molecular structure on the stability of water in oil emulsion

2021 ◽  
Vol 196 ◽  
pp. 107695
Author(s):  
Guangsheng Cao ◽  
Tong Du ◽  
Yujie Bai ◽  
Tingyuan Yang ◽  
Jize Zuo
Keyword(s):  
Molecular Structure ◽  
Oil Emulsion ◽  
The Stability ◽  
Stability Of Water ◽  
Water In Oil Emulsion

scholarly journals Molecular structure of an N-terminal phosphorylated β-amyloid fibril

2019 ◽  
Vol 116 (23) ◽  
pp. 11253-11258 ◽  
Author(s):  
Zhi-Wen Hu ◽  
Liliya Vugmeyster ◽  
Dan Fai Au ◽  
Dmitry Ostrovsky ◽  
Yan Sun ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Amyloid Fibril ◽  
Amyloid Plaques ◽  
Wild Type ◽  
Structural Polymorphism ◽  
Significant Difference ◽  
Amyloid Aβ ◽  
Β Amyloid ◽  
The Stability ◽  
Seeding Efficiency

The structural polymorphism in β-amyloid (Aβ) plaques from Alzheimer disease (AD) has been recognized as an important pathological factor. Plaques from sporadic AD patients contain fibrillar deposits of various amyloid proteins/peptides, including posttranslational modified Aβ (PTM-Aβ) subtypes. Although many PTM-Aβs were shown to accelerate the fibrillation process, increase neuronal cytotoxicity of aggregates, or enhance the stability of fibrils, the contribution of PTM-Aβs to structural polymorphisms and their pathological roles remains unclear. We report here the NMR-based structure for the Ser-8-phosphorylated 40-residue Aβ (pS8-Aβ40) fibrils, which shows significant difference to the wild-type fibrils, with higher cross-seeding efficiency and thermodynamic stability. Given these physicochemical properties, the structures originated from pS8-Aβ40 fibrils may potentially dominate the polymorphisms in the mixture of wild-type and phosphorylated Aβ deposits. Our results imply that Aβ subtypes with “seeding-prone” properties may influence the polymorphisms of amyloid plaques through the cross-seeding process.

Eine neuartige Assoziation zwischen Kalium und komplex gebundenem DistickstofF -Struktur von KN2Co(PMe3)3 /A Novel Association of Potassium and Co-ordinated Dinitrogen - Crystal Structure of KN2Co(PMe3)3

1978 ◽  
Vol 33 (11) ◽  
pp. 1267-1273 ◽  
Author(s):  
Hans-Friedrich Klein ◽  
Reinhard Hammer ◽  
Josef Wenninger ◽  
Peter Friedrich ◽  
Gottfried Huttner
Keyword(s):  
Molecular Structure ◽  
Allyl Bromide ◽  
Molecular Nitrogen ◽  
Ambient Conditions ◽  
Oxidative Additions ◽  
Novel Association ◽  
Cluster A ◽  
The Stability ◽  
Ether Solvents ◽  
Infrared Data

Abstract[(Me3P)3CoN2]2Mg(THF)4 reacts with potassium metal to give [KN2Co(PMe3)3]6. The same compound is obtained via substitution of olefin in cobaltates K+[Co(olefin)(PMe3)3]- by molecular nitrogen under ambient conditions. Infrared data show that association is preserved even in ether solvents. The stability of cobaltates [Co(PMe3)3L]- increases in the order L = olefin < dinitrogen < PMe3.Reactions of the title compound proceed as oxidative additions to the monomer with loss of molecular nitrogen. Methyl iodide and allyl bromide yield the fluxional complexes CoCH3(PMe3)4 and η3-C3H5Co(PMe3)3, respectively. Ethyl bromide givescis-CoH(C2H4)(PMe3)3 via β-elimination and coordination of ethylene. The molecular structure of [KN2Co(PMe3)3]6 reveals a novel type of cluster: a double cube made up from six KN2 units with six exo-Co(PMe3)3 groups (d(NN) = 116-118 pm, d(CoN) = 170-171 pm).

scholarly journals Stabilization of nucleic acids by unusual polyamines produced by an extreme thermophile, Thermus thermophilus

2005 ◽  
Vol 388 (2) ◽  
pp. 427-433 ◽  
Author(s):  
Yusuke TERUI ◽  
Mio OHNUMA ◽  
Kaori HIRAGA ◽  
Etsuko KAWASHIMA ◽  
Tairo OSHIMA
Keyword(s):  
Molecular Structure ◽  
Thermal Denaturation ◽  
Thermus Thermophilus ◽  
Amino Nitrogen ◽  
The Other ◽  
Extreme Thermophile ◽  
Scanning Calorimetry ◽  
Extreme Thermophiles ◽  
The Stability ◽  
Ammonium Compounds

Extreme thermophiles produce two types of unusual polyamine: long linear polyamines such as caldopentamine and caldohexamine, and branched polyamines such as quaternary ammonium compounds [e.g. tetrakis(3-aminopropyl)ammonium]. To clarify the physiological roles of long linear and branched polyamines in thermophiles, we synthesized them chemically and tested their effects on the stability of ds (double-stranded) and ss (single-stranded) DNAs and tRNA in response to thermal denaturation, as measured by differential scanning calorimetry. Linear polyamines stabilized dsDNA in proportion to the number of amino nitrogen atoms within their molecular structure. We used the empirical results to derive formulae that estimate the melting temperature of dsDNA in the presence of polyamines of a particular molecular composition. ssDNA and tRNA were stabilized more effectively by tetrakis(3-aminopropyl)ammonium than any of the other polyamines tested. We propose that long linear polyamines are effective to stabilize DNA, and tetrakis(3-aminopropyl)ammonium plays important roles in stabilizing RNAs in thermophile cells.

Theoretical study of the molecular structure and the stability of neutral and reduced tetracyanoethylene

2003 ◽  
Vol 375 (3-4) ◽  
pp. 376-382 ◽  
Author(s):  
Begoña Milián ◽  
Rosendo Pou-Amérigo ◽  
Rafael Viruela ◽  
Enrique Ortı́
Keyword(s):  
Molecular Structure ◽  
Theoretical Study ◽  
The Stability

Effect of pH on the stability and molecular structure of nitrosyl hemochromogen

2016 ◽  
Vol 196 ◽  
pp. 503-508 ◽  
Author(s):  
Chensha Yu ◽  
Jingzhi Jiao ◽  
Lizhen Ma ◽  
Weiqing Sun
Keyword(s):  
Molecular Structure ◽  
Effect Of Ph ◽  
The Stability

scholarly journals Theoretical Investigation on Molecular Structure and Electronic Properties of BxLiy Cluster for Lithium-Ion Batteries with Quantum ESPRESSO Program

Molecules ◽  
2020 ◽  
Vol 25 (14) ◽  
pp. 3266
Author(s):  
Mustafa Ali Çipiloğlu ◽  
Ali Özkurt
Keyword(s):  
Molecular Structure ◽  
Electronic Properties ◽  
Molecular Orbital ◽  
Dissociation Energy ◽  
Point Group ◽  
Lithium Ion ◽  
Binding Energies ◽  
Geometrical Structures ◽  
The Stability ◽  
Quantum Espresso

In this study, molecular structure and electronic properties of eleven BxLiy (x = 1–3, y = 1–3) clusters are examined using the Perdew, Burke and Ernezerhof (PBE) method in the Quantum ESPRESSO program. Three main groups, consisting of two atoms, three atoms and four atoms, are selected as the starting points. The stable configurations, their binding energies per atom (Eb), dissociation energy (ΔE), and the second difference in energy (Δ2E), HOMO-LUMO (HOMO: Highest Occupied Molecular Orbital LUMO: Lowest Occupied Molecular Orbital) gaps, total energy, frequency, force on atom, point group, bond length, density of state (DOS) and band structures are investigated for BxLiy (x = 1–3, y = 1–3) clusters. The results of binding energies (Eb), dissociation energy (ΔE) and the second difference in energy (Δ2E) show that BLi, BLi2 first isomer, BLi2 second isomer, B2Li2 first isomer, B2Li2 second isomer and BLi3 are the most stable among all 11 molecules of BxLiy (x = 1–3, y = 1–3). The stability of BxLiy (x = 1–3, y = 1–3) clusters depend on both the formation of geometrical structures on the number of Li atoms. As the number of Li atoms in the group increases, the stability of BxLiy clusters also increases. Within each group formation of geometrical structures, the stability of BxLiy clusters changes. It is observed that they may change the capability of chemical reactions in BxLiy clusters.

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