Sergei A. Egorov
Professor, Chemistry
Bio & Overview
Structure and Dynamics in Supercritical Fluids
Supercritical fluids (SCFs) are currently receiving much industrial and scientific interest as a result of their unique physical properties. The most characteristic features of SCFs are liquid-like densities, gas-like viscosities, and diffusivities that are intermediate between typical gas and liquid values. The resulting combination of high dissolving power and enhanced mass-transfer rates makes SCFs attractive alternatives to liquid solvents for a variety of industrial applications, such as extraction, separation and reaction processes. In addition, the high compressibility of SCFs in the near-critical region allows one to tune their properties to desired values by applying small changes in pressure, which in turn makes it possible to tailor the rates and selectivities of chemical processes. Since the aforementioned applications of SCFs generally involve dilute solutions, it is essential to develop a microscopic understanding of the structure and dynamics of a supercritical solvent in the vicinity of a solute.
We use the methods of classical statistical mechanics, such as integral equation theory and mode coupling theory, to study structural and dynamical properties of supercritical solutions. Some of the problems we address are as follows. How does the solvent-solute and solute-solute clustering affect the rates and equilibrium constants of chemical reactions in SCFs? How does the proximity to the critical point affect the transport properties and what are the ramifications for diffusion controlled chemical reactions? How is preferential solvation manifested in local composition effects in dilute supercritical solutions? The answers to these questions should help us shed further light on fundamental properties of SCFs and their practical applications.
Quantum and Semiclassical Many-Body Dynamics
Numerous problems in chemical physics involve calculations of quantum time correlation functions (TCFs) in many-body systems. Particular examples include: medium-induced electron transfer, dissipative tunneling, radiationless processes, and electronic spectroscopy of chromophores in crystals and in liquids. While certain systems require a fully quantum mechanical treatment, there exists a large class of systems of chemical interest for which classical mechanics provides a reasonably good approximation. An appealing approach to the calculation of TCFs for such systems involves using semiclassical methods, which are generally based on the assumption that quantum effects can be taken into account by introducing relatively small corrections to the classical results. However, the shorter the time scale on which the behavior is analyzed, the more important quantum corrections may become, even for systems which are classical as far as their static and low-frequency dynamical properties are concerned. One of the research projects in our group involves developing a systematic procedure for including quantum effects into the results for TCFs obtained from classical simulations.
An alternative approach to study quantum dynamics in condensed phases involves calculating imaginary-time correlation functions using path integral Monte Carlo (PIMC) method and performing analytic continuation to the real-time axis. Unfortunately, analytic continuation is numerically unstable, and therefore leads to uncontrollable amplification of statistical noise unavoidable in PIMC simulations. In our group we employ the information theory and the methodology from the field of inverse problems in order to develop various techniques, such as Maximum Entropy and Singular Value Decomposition, for stabilizing the procedure of analytic continuation of quantum imaginary-time TCFs.
Academic Information
- Department
- Chemistry
- Academic Title
- Professor
Research Interests
Research Disciplines
- Chemistry
Selected Publications
2022
Egorov, S. A. (2022). Bulk phase behavior and interfacial properties of binary mixtures of Lennard-Jones chains and solvent: a density functional theory study. SOFT MATTER, 18(5), 1034-1043. doi:10.1039/d1sm01722e
Egorov, S. A. (2022). Bulk and interfacial properties of semiflexible polymers: A density functional theory study. JOURNAL OF MOLECULAR LIQUIDS, 356. doi:10.1016/j.molliq.2022.119025
Theodorakis, P. E., Egorov, S. A., & Milchev, A. (2022). Rugotaxis: Droplet motion without external energy supply. EPL, 137(4). doi:10.1209/0295-5075/ac55f2
2021
Egorov, S. A. (2021). Interactions between Sterically Stabilized Nanoparticles: The Effects of Brush Bidispersity and Chain Stiffness. POLYMERS, 13(14). doi:10.3390/polym13142296
2020
Binder, K., Egorov, S. A., Milchev, A., & Nikoubashman, A. (2020). Understanding the properties of liquid-crystalline polymers by computational modeling. JOURNAL OF PHYSICS-MATERIALS, 3(3). doi:10.1088/2515-7639/ab975e
2019
Chen, R., Poling-Skutvik, R., Howard, M. P., Nikoubashman, A., Egorov, S. A., Conrad, J. C., & Palmer, J. C. (2019). Influence of polymer flexibility on nanoparticle dynamics in semidilute solutions. SOFT MATTER, 15(6), 1260-1268. doi:10.1039/c8sm01834k
Wang, S. -J., Venkateshvaran, D., Mahani, M. R., Chopra, U., McNellis, E. R., Di Pietro, R., . . . Sirringhaus, H. (2019). Long spin diffusion lengths in doped conjugated polymers due to enhanced exchange coupling (vol 2, pg 98, 2019). NATURE ELECTRONICS, 2(7), 313. doi:10.1038/s41928-019-0243-0
Merz, S. N., Hoover, E., Egorov, S. A., DuBay, K. H., & Green, D. L. (2019). Predicting the effect of chain-length mismatch on phase separation in noble metal nanoparticle monolayers with chemically mismatched ligands. SOFT MATTER, 15(22), 4498-4507. doi:10.1039/c9sm00264b
2018
Milchev, A., Egorov, S. A., Binder, K., & Nikoubashman, A. (2018). Nematic order in solutions of semiflexible polymers: Hairpins, elastic constants, and the nematic-smectic transition. JOURNAL OF CHEMICAL PHYSICS, 149(17). doi:10.1063/1.5049630
Das, S. K., Egorov, S. A., Virnau, P., Winter, D., & Binder, K. (2018). Do the contact angle and line tension of surface-attached droplets depend on the radius of curvature?. JOURNAL OF PHYSICS-CONDENSED MATTER, 30(25). doi:10.1088/1361-648X/aac363
Milchev, A., Egorov, S. A., Vega, D. A., Binder, K., & Nikoubashman, A. (2018). Densely Packed Semiflexible Macromolecules in a Rigid Spherical Capsule. MACROMOLECULES, 51(5), 2002-2016. doi:10.1021/acs.macromol.7b02643
Milchev, A., Egorov, S. A., Nikoubashman, A., & Binder, K. (2018). Adsorption and structure formation of semiflexible polymers on spherical surfaces. POLYMER, 145, 463-472. doi:10.1016/j.polymer.2018.04.054
Klop, K. E., Dullens, R. P. A., Lettinga, M. P., Egorov, S. A., & Aarts, D. G. A. L. (2018). Capillary nematisation of colloidal rods in confinement. MOLECULAR PHYSICS, 116(21-22), 2864-2871. doi:10.1080/00268976.2018.1497210
2017
Theodorakis, P. E., Egorov, S. A., & Milchev, A. (2017). Stiffness-guided motion of a droplet on a solid substrate. JOURNAL OF CHEMICAL PHYSICS, 146(24). doi:10.1063/1.4990436
Milchev, A., Egorov, S. A., Nikoubashman, A., & Binder, K. (2017). Conformations and orientational ordering of semiflexible polymers in spherical confinement. JOURNAL OF CHEMICAL PHYSICS, 146(19). doi:10.1063/1.4983131
Popova, H., Milchev, A., & Egorov, S. A. (2017). Modeling the interfacial tension dependence on composition and stiffness of nonionic surfactants on liquid-liquid interfaces. COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS, 519, 168-178. doi:10.1016/j.colsurfa.2016.05.056
Milchev, A., Egorov, S. A., & Binder, K. (2017). Semiflexible polymers confined in a slit pore with attractive walls: two-dimensional liquid crystalline order versus capillary nematization. SOFT MATTER, 13(9), 1888-1903. doi:10.1039/c7sm00105c
2016
Merz, S. N., Farrell, Z. J., Dunn, C. J., Swanson, R. J., Egorov, S. A., & Green, D. L. (2016). Theoretical and Experimental Investigation of Microphase Separation in Mixed Thiol Monolayers on Silver Nanoparticles. ACS NANO, 10(11), 9871-9878. doi:10.1021/acsnano.6b02091
Egorov, S. A., Milchev, A., & Binder, K. (2017). Capillary Nematization of Semiflexible Polymers. MACROMOLECULAR THEORY AND SIMULATIONS, 26(1). doi:10.1002/mats.201600036
Egorov, S. A., Milchev, A., & Binder, K. (2016). Semiflexible Polymers in the Bulk and Confined by Planar Walls. POLYMERS, 8(8). doi:10.3390/polym8080296
Egorov, S. A., Milchev, A., Virnau, P., & Binder, K. (2016). A new insight into the isotropic-nematic phase transition in lyotropic solutions of semiflexible polymers: density-functional theory tested by molecular dynamics. SOFT MATTER, 12(22), 4944-4959. doi:10.1039/c6sm00778c
Egorov, S. A., Milchev, A., & Binder, K. (2016). Anomalous Fluctuations of Nematic Order in Solutions of Semiflexible Polymers. PHYSICAL REVIEW LETTERS, 116(18). doi:10.1103/PhysRevLett.116.187801
Egorov, S. A., Milchev, A., Virnau, P., & Binder, K. (2016). Semiflexible polymers under good solvent conditions interacting with repulsive walls. JOURNAL OF CHEMICAL PHYSICS, 144(17). doi:10.1063/1.4947254
Trefz, B., Das, S. K., Egorov, S. A., Virnau, P., & Binder, K. (2016). Activity mediated phase separation: Can we understand phase behavior of the nonequilibrium problem from an equilibrium approach?. JOURNAL OF CHEMICAL PHYSICS, 144(14). doi:10.1063/1.4945365
Poier, P., Egorov, S. A., Likos, C. N., & Blaak, R. (2016). Concentration-induced planar-to-homeotropic anchoring transition of stiff ring polymers on hard walls. SOFT MATTER, 12(38), 7983-7994. doi:10.1039/c6sm01453d
2015
Riest, J., Athanasopoulou, L., Egorov, S. A., Likos, C. N., & Ziherl, P. (2015). Elasticity of polymeric nanocolloidal particles. SCIENTIFIC REPORTS, 5. doi:10.1038/srep15854
Farrell, Z., Merz, S., Seager, J., Dunn, C., Egorov, S., & Green, D. L. (2015). Development of Experiment and Theory to Detect and Predict Ligand Phase Separation on Silver Nanoparticles. ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 54(22), 6479-6482. doi:10.1002/anie.201500906
Egorov, S. A., Hsu, H. -P., Milchev, A., & Binder, K. (2015). Semiflexible polymer brushes and the brush-mushroom crossover. SOFT MATTER, 11(13), 2604-2616. doi:10.1039/c4sm02862g
2014
Das, S. K., Egorov, S. A., Trefz, B., Virnau, P., & Binder, K. (2014). Phase Behavior of Active Swimmers in Depletants: Molecular Dynamics and Integral Equation Theory. PHYSICAL REVIEW LETTERS, 112(19). doi:10.1103/PhysRevLett.112.198301
Milchev, A., Egorov, S. A., & Binder, K. (2014). Critical adsorption of a single macromolecule in polymer brushes. SOFT MATTER, 10(32), 5974-5990. doi:10.1039/c4sm00688g
2013
Dutta, N., Egorov, S., & Green, D. (2013). Quantification of Nanoparticle Interactions in Pure Solvents and a Concentrated PDMS Solution as a Function of Solvent Quality. LANGMUIR, 29(32), 9991-10000. doi:10.1021/la303495a
Cao, X. -Z., Merlitz, H., Wu, C. -X., Egorov, S. A., & Sommer, J. -U. (2013). Effective pair potentials between nanoparticles induced by single monomers and polymer chains. SOFT MATTER, 9(25), 5916-5926. doi:10.1039/c3sm50495f
Leermakers, F. A. M., & Egorov, S. A. (2013). On the collapse transition of a polymer brush: the case of lateral mobility. SOFT MATTER, 9(12), 3341-3348. doi:10.1039/c3sm27586h
Paturej, J., Milchev, A., Egorov, S. A., & Binder, K. (2013). The Escape Transition of a Compressed Star Polymer: Self-Consistent Field Predictions Tested by Simulation. MACROMOLECULES, 46(19), 8009-8016. doi:10.1021/ma401356w
Paturej, J., Milchev, A., Egorov, S. A., & Binder, K. (2013). Star polymers confined in a nanoslit: a simulation test of scaling and self-consistent field theories. SOFT MATTER, 9(44), 10522-10531. doi:10.1039/c3sm51275d
Egorov, S. A., Paturej, J., Likos, C. N., & Milchev, A. (2013). Controlling the Interactions between Soft Colloids via Surface Adsorption. MACROMOLECULES, 46(9), 3648-3653. doi:10.1021/ma400188s
2012
Egorov, S. A. (2012). Insertion of nanoparticles into polymer brush under variable solvent conditions. JOURNAL OF CHEMICAL PHYSICS, 137(13). doi:10.1063/1.4757017
Egorov, S. A., & Binder, K. (2012). Effect of solvent quality on the dispersibility of polymer-grafted spherical nanoparticles in polymer solutions. JOURNAL OF CHEMICAL PHYSICS, 137(9). doi:10.1063/1.4747196
Egorov, S. A., Romeis, D., & Sommer, J. -U. (2012). Surface instabilities of minority chains in dense polymer brushes: A comparison of density functional theory and quasi-off-lattice self-consistent field theory. JOURNAL OF CHEMICAL PHYSICS, 137(6). doi:10.1063/1.4742934
Lo Verso, F., Yelash, L., Egorov, S. A., & Binder, K. (2012). Effect of the solvent quality on the structural rearrangement of spherical brushes: coarse-grained models. SOFT MATTER, 8(15), 4185-4196. doi:10.1039/c2sm06836b
Camargo, M., Egorov, S. A., & Likos, C. N. (2012). Cluster formation in star-linear polymer mixtures: equilibrium and dynamical properties. SOFT MATTER, 8(15), 4177-4184. doi:10.1039/c2sm06849d
Wang, R., Egorov, S. A., Milchev, A., & Binder, K. (2012). Stretching of Free Chains Confined in Concave Brush-Coated Nanocylinders. MACROMOLECULES, 45(5), 2580-2587. doi:10.1021/ma202620z
LoVerso, F., Egorov, S. A., & Binder, K. (2012). Interaction Between Polymer Brush-Coated Spherical Nanoparticles: Effect of Solvent Quality. MACROMOLECULES, 45(21), 8892-8902. doi:10.1021/ma301651z
Egorov, S. A. (2012). Microphase separation of mixed polymer brushes physisorbed on cylindrical surfaces. SOFT MATTER, 8(14), 3971-3979. doi:10.1039/c2sm07266a
2011
Lo Verso, F., Yelash, L., Egorov, S. A., & Binder, K. (2011). Interactions between polymer brush-coated spherical nanoparticles: The good solvent case. JOURNAL OF CHEMICAL PHYSICS, 135(21). doi:10.1063/1.3663964
Egorov, S. A. (2011). Hydrophobic interactions with coarse-grained model for water. JOURNAL OF CHEMICAL PHYSICS, 134(23). doi:10.1063/1.3602217
Egorov, S. A. (2011). Sterically stabilized lock and key colloids: A self-consistent field theory study. JOURNAL OF CHEMICAL PHYSICS, 134(19). doi:10.1063/1.3591970
Egorov, S. A. (2011). Anomalous nanoparticle diffusion in polymer solutions and melts: A mode-coupling theory study. JOURNAL OF CHEMICAL PHYSICS, 134(8). doi:10.1063/1.3556749
McEwan, M. E., Egorov, S. A., Ilavsky, J., Green, D. L., & Yang, Y. (2011). Mechanical reinforcement of polymer nanocomposites: theory and ultra-small angle X-ray scattering (USAXS) studies. SOFT MATTER, 7(6), 2725-2733. doi:10.1039/c0sm00393j
Egorov, S. A., Milchev, A., Klushin, L., & Binder, K. (2011). Structural properties of concave cylindrical brushes interacting with free chains. SOFT MATTER, 7(12), 5669-5676. doi:10.1039/c1sm05139c
2010
Lo Verso, F., Egorov, S. A., Milchev, A., & Binder, K. (2010). Spherical polymer brushes under good solvent conditions: Molecular dynamics results compared to density functional theory. JOURNAL OF CHEMICAL PHYSICS, 133(18). doi:10.1063/1.3494902
Shall, L. A., & Egorov, S. A. (2010). Structural and dynamical anomalies of a Gaussian core fluid: A mode-coupling theory study. JOURNAL OF CHEMICAL PHYSICS, 132(18). doi:10.1063/1.3429354
Milchev, A., Egorov, S. A., & Binder, K. (2010). Absorption/expulsion of oligomers and linear macromolecules in a polymer brush. JOURNAL OF CHEMICAL PHYSICS, 132(18). doi:10.1063/1.3414996