The quantum-chemical approach to calculations of thermodynamic and structural parameters of formation of fatty acid monolayers with hexagonal packing at the air/water interface

2014 ◽  
Vol 16 (7) ◽  
pp. 3187 ◽  
Author(s):  
Yu. B. Vysotsky ◽  
E. A. Belyaeva ◽  
E. S. Fomina ◽  
D. Vollhardt ◽  
V. B. Fainerman ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Quantum Chemical ◽  
Structural Parameters ◽  
Water Interface ◽  
Hexagonal Packing ◽  
Chemical Approach ◽  
Air Water Interface ◽  
Quantum Chemical Approach

On Hexagonal Orientation of Fatty Alcohols in Monolayers at the Air/Water Interface: Quantum-Chemical Approach

2014 ◽  
Vol 118 (8) ◽  
pp. 4122-4130 ◽  
Author(s):  
Elena S. Fomina ◽  
Yuri B. Vysotsky ◽  
Elena A. Belyaeva ◽  
Dieter Vollhardt ◽  
Valentin B. Fainerman ◽  
...  
Keyword(s):  
Quantum Chemical ◽  
Fatty Alcohols ◽  
Water Interface ◽  
Chemical Approach ◽  
Air Water Interface ◽  
Quantum Chemical Approach

Temperature Effect on the Monolayer Formation of Substituted Alkanes at the Air/Water Interface: A Quantum Chemical Approach

2012 ◽  
Vol 116 (30) ◽  
pp. 8996-9006 ◽  
Author(s):  
Yu. B. Vysotsky ◽  
E. S. Fomina ◽  
E. A. Belyaeva ◽  
D. Vollhardt ◽  
V. B. Fainerman ◽  
...  
Keyword(s):  
Temperature Effect ◽  
Quantum Chemical ◽  
Water Interface ◽  
Monolayer Formation ◽  
Chemical Approach ◽  
Air Water Interface ◽  
Quantum Chemical Approach ◽  
Substituted Alkanes

scholarly journals Surface pKa of Saturated Carboxylic Acids at the Air/Water Interface: A Quantum Chemical Approach

2020 ◽  
Vol 124 (25) ◽  
pp. 13809-13818
Author(s):  
Yuri B. Vysotsky ◽  
Elena S. Kartashynska ◽  
Dieter Vollhardt ◽  
Valentin B. Fainerman
Keyword(s):  
Carboxylic Acids ◽  
Quantum Chemical ◽  
Water Interface ◽  
Chemical Approach ◽  
Air Water Interface ◽  
Quantum Chemical Approach

scholarly journals PK CHANGE OF SATURATED CARBOXYLIC ACIDS AND AMINES DURING THEIR DIMERIZATION AT THE AIR/WATER INTERFACE. QUANTUM-CHEMICAL APPROACH

2020 ◽  
pp. 370-383
Author(s):  
Юрий Борисович Высоцкий ◽  
Елена Сергеевна Карташинская
Keyword(s):  
Carboxylic Acids ◽  
Quantum Chemical ◽  
Water Interface ◽  
Gas Phases ◽  
Screening Model ◽  
Gibbs Energies ◽  
Quantum Chemical Methods ◽  
Air Water Interface ◽  
Quantum Chemical Approach ◽  
Semi Empirical

Предложен теоретический подход к оценке pK димеров насыщенных карбоновых кислот CHCOOH и аминов CHNH (n = 6-16) на межфазной поверхности вода/воздух. Модель основана на расчете лишь энергий Гиббса образования и ассоциации димеров ПАВ в нейтральной и ионизированной форме в водной и газовой фазах. Расчеты проведены с использованием полуэмпирического квантово-химического метода РМ3 и РМ6 в рамках модели экранирования проводникового типа COSMO. Показано, что наиболее энергетически выгодным является образование димеров с одной ионизированной и одной нейтральной молекулой ПАВ. Установлено, что величина поверхностного pK для димеров ПАВ зависит от их длины цепи ПАВ. A theoretical approach to the pK assessment for dimers of saturated carboxylic acids CHCOOH (n = 6 -16) and amines CHNH (n = 6-16) at the air/water interface is proposed. The model is based on calculation of the formation and dimerization Gibbs energies of the surfactants in neutral and ionized form in the water and gas phases. The calculations are done using semi-empirical quantum-chemical methods РМ3 and РМ6 within the framework of the conductor-like screening model (COSMO). It is shown that the dimer formation with one ionized and one neutral surfactant molecules is the most energetically favorable. The surface pK value for surfactant dimers is found to depend on their surfactant chain length.

Metastability in Monolayer Films Transferred onto Solid Substrates by the Langmuir-Blodgett Method: IR Evidence for Transfer-Induced Phase Transitions

1994 ◽  
Vol 48 (10) ◽  
pp. 1196-1203 ◽  
Author(s):  
Fazale R. Rana ◽  
Suci Widayati ◽  
Brian W. Gregory ◽  
Richard A. Dluhy
Keyword(s):  
Fatty Acid ◽  
Conformational Changes ◽  
Structural Changes ◽  
High Surface ◽  
Solid Substrate ◽  
Water Interface ◽  
Monolayer Films ◽  
Langmuir Blodgett ◽  
Monomolecular Film ◽  
Air Water Interface

The rate at which a monomolecular film is deposited onto a solid substrate in the Langmuir-Blodgett process of preparing supported monolayer films influences the final structure of the transferred film. Attenuated total reflectance infrared spectroscopic studies of monolayers transferred to germanium substrates show that the speed at which the substrate is drawn through the air/water interface influences the final conformation in the hydrocarbon chains of amphiphilic film molecules. This transfer-induced effect is especially evident when the monolayer is transferred from the expanded region of surface-pressure-molecular-area isotherms at low surface pressures; the effect is minimized when the film molecules are transferred from condensed phases at high surface pressures. This phenomenon has been observed for both a fatty acid and a phospholipid, which suggests that these conformational changes may occur in a variety of hydrocarbon amphiphiles transferred from the air/water interface. This conformational ordering may be due to a kinetically limited phase transition taking place in the meniscus formed between the solid substrate and aqueous subphase. In addition, the results obtained for both the phospholipid and fatty acid suggest that the structure of the amphiphile may help determine the extent and nature of the transfer-speed-induced structural changes taking place in the monomolecular film.

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