TY  - JOUR
A1  - Poghosyan, Armen H.
A1  - Shahinyan, A. A.
A1  - Koetz, Joachim
T1  - Self-assembled monolayer formation of distorted cylindrical AOT micelles on gold surfaces
JF  - Colloids and surfaces : an international journal devoted to the principles and applications of colloid and interface science ; A, Physicochemical and engineering aspects
N2  - Self-assembling features of sodium dioctyl sulfosuccinate (AOT) molecules and micelle adsorption on gold Au (111) surfaces have been examined using molecular dynamics simulation. We argue that AOT micelles display a strong adsorption on gold surfaces resulting in distorted cylindrical micelles attached to the (111) facets. The well protected Au(111) facets decorated by a dense packed elongated ellipsoidal AOT layer hinder the diffusion of the reactant to the (111) facets and could result in the preferential growth of ultra-thin gold nanoplatelets.
KW  - Surfactant micelles
KW  - Adsorption
KW  - Gold surface
KW  - Molecular dynamics
Y1  - 2018
U6  - https://doi.org/10.1016/j.colsurfa.2018.02.067
SN  - 0927-7757
SN  - 1873-4359
VL  - 546
SP  - 20
EP  - 27
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Poghosyan, Armen H.
A1  - Arsenyan, Levon H.
A1  - Antonyan, Lilit A.
A1  - Shahinyan, Aram A.
A1  - Koetz, Joachim
T1  - Molecular dynamics simulations of branched polyethyleneimine in water-in-heptanol micelles stabilized by zwitterionic surfactants
JF  - Colloids and surfaces : an international journal devoted to the principles and applications of colloid and interface science ; A, Physicochemical and engineering aspects
N2  - We have performed a 50 ns molecular dynamics simulation of a hyperbranched polymer, i.e. polyethyleneimine (PEI), inside inverse micelles formed with zwitterionic surfactants 3-(N, N-dimethyldodecylammoniio)-propansulfonate (SB) in heptanol. The runs were performed using the GROMACS simulation package. During simulation time the PEI molecule undergoes a conformational deformation and compaction. The radius of gyration of the PEI molecule finally located in the center of the water droplet is decreased from 3 nm to 1.7 nm. The unusual shrinking of the PEI molecule inside the micelle explains the extraordinary template effect of these microemulsions by making cadmium sulfide or gold clusters. (C) 2015 Elsevier B.V. All rights reserved.
KW  - Surfactant micelles
KW  - Molecular dynamics simulations
KW  - Polyethyleneimine
Y1  - 2015
U6  - https://doi.org/10.1016/j.colsurfa.2015.03.053
SN  - 0927-7757
SN  - 1873-4359
VL  - 479
SP  - 18
EP  - 24
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Poghosyan, Armen H.
A1  - Arsenyan, Levon H.
A1  - Gharabekyan, Hrant H.
A1  - Falkenhagen, Sandra
A1  - Koetz, Joachim
A1  - Shahinyan, Aram A.
T1  - Molecular dynamics simulations of inverse sodium dodecyl sulfate (SDS) micelles in a mixed toluene/pentanol solvent in the absence and presence of poly(diallyldimethylammonium chloride) (PDADMAC)
JF  - Journal of colloid and interface science
N2  - We have performed a 15 ns molecular dynamics simulation of inverse sodium dodecyl sulfate (SDS) micelles in a mixed toluene/pentanol solvent in the absence and presence of a cationic polyelectrolyte, i.e. poly(diallyldimethylammonium chloride) (PDADMAC). The NAMD code and CHARMM force field were used. During the simulation time, the radii of SOS inverse micelles changed and the radii of the water droplets have been calculated. The behavior of SDS hydrocarbon chains has been characterized by calculating the orientation order parameter and the chain average length. The water droplet properties (water flow, water molecules displacement) have been examined. In summary the MD simulations indicate a more rigid and ordered surfactant film due to the formation of a polyelectrolyte palisade layer in full agreement with the experimental findings, e.g. the viscosity increase and shift of the percolation boundary.
KW  - Surfactant micelles
KW  - Molecular dynamics simulations
KW  - SDS
Y1  - 2011
U6  - https://doi.org/10.1016/j.jcis.2011.01.091
SN  - 0021-9797
VL  - 358
IS  - 1
SP  - 175
EP  - 181
PB  - Elsevier
CY  - San Diego
ER  -