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Surfactants in non-polar solvents can form reverse micelles. In this work, we report results of the study of transport properties of the solution of nonionic surfactant C12E4 in heptane. For all considered systems, we performed all-atom molecular dynamics simulations in NPT statistical ensemble. The all-atom models were created using the CGenFF 4.4 force field [1]. To find the viscosities of colloid systems via molecular dynamics simulations, one can employ the StokesEinstein formula [2,3]. Palmer proposed an alternative method [4] based on the calculation of autocorrelation functions of the momentum. We used Palmer’s method implemented in GROMACS 2020.1 package [5] to find the viscosities of one-component liquids (water, pentane, heptane, decane) and two-component systems consisting of hydrocarbon (heptane) and a C12E4 aggregate. In particular, viscosities of the systems containing inverse premicellar aggregates with 2, 4, 8, 16 and 25 C12E4 molecules were estimated. Our results for one-component systems are consistent with previous works of other authors. For water systems, the agreement with the results of the molecular dynamics simulation in [6] was observed. The results of the viscosity calculation for pentane matched well those from [7]. For the system containing decane, the agreement with the experimental data from [8] was observed. For the systems containing inverse micelles, we also used the Stokes-Einstein formula to estimate the viscosities. The StokesEinstein formula relates the viscosity of the liquid media with the size of a spherical particle in it and the particle’s diffusion coefficient. The in-house programs were used to analyze the obtained molecular dynamics trajectories and to calculate the average radii of inverse premicellar aggregates and their diffusion coefficients. Thus, the dependence of viscosity on the total surfactant concentration was obtained by two different methods.
Original languageEnglish
Title of host publicationXXIII International Conference on Chemical Thermodynamics in Russia, RCCT-2022 August 22-26, 2022, Kazan, Russia: Abstracts.
Place of PublicationKazan
PublisherКазанский Федеральный университет
Pages289
Number of pages1
StatePublished - Aug 2022
EventXXIII International Conference on Chemical Thermodynamics in Russia - Казанский (Приволжский) федеральный университет, Казань, Russian Federation
Duration: 22 Aug 202227 Aug 2022
Conference number: 23
https://rcct2021.kpfu.ru/

Conference

ConferenceXXIII International Conference on Chemical Thermodynamics in Russia
Abbreviated titleRCCT-2022
Country/TerritoryRussian Federation
CityКазань
Period22/08/2227/08/22
Internet address

    Scopus subject areas

  • Physics and Astronomy(all)

ID: 98121129