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Lab team

Our laboratory of digital materials Science is engaged in the development and application of quantum chemical methods for modeling various systems at the molecular level. Our research is aimed at solving a wide range of problems related to the study of the mechanisms of chemical reactions, properties of crystals, nanomaterials and biomolecules.

The scientific group, consisting of highly qualified scientists, researchers and students, works using advanced methods of quantum chemical modeling and a variety of software such as VASP, Siesta, LAMMPS, Gaussian, etc.

​The laboratory's research activities include conducting experiments and analyzing results using computational chemistry and quantum mechanics methods. We are engaged in modeling chemical reactions, quantifying stability, predicting the properties of materials, analyzing electronic structures, determining the parameters of crystalline and molecular structures, studying the binding of drugs to carriers, and the like.

  1. DFT calculations
  2. Molecular dynamics and quantum chemical calculations
  3. Quantum molecular dynamics
  4. Theory of Quantum Mechanics/Molecular Mechanics (KM/MM)
Pavel Sorokin 🥼 🤝
Head of Laboratory
Liubov Antipina 🥼 🤝
Senior Researcher
Konstantin Larionov 🤝 🥼
Junior researcher

Research directions

A promising sorbent for wastewater treatment from antibiotics has been proposed

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The article was published in the journal Nanomaterials. As a result of the constant growth in the use of medicines, the accumulation of antibiotics and their decomposition products in wastewater has become a serious problem for humans and the environment. Most often, antibiotics enter rivers and groundwater as waste from pharmaceutical enterprises, medical and pharmacy institutions, and agriculture. The presence of antibiotics in water leads to an increase in the resistance of bacteria and microorganisms to them, the development of allergic reactions, and even the proliferation of dangerous bacteria. Currently, there are various methods of wastewater treatment, however, each method has its own limitations. Sorption is one of the simplest and most inexpensive cleaning methods that do not require complex production structures or additional chemical reactions. The staff of the Laboratory of Digital Materials Science and the research center "Inorganic Nanomaterials" of NUST MISIS focused on it. For the proposed method, there is no need to create special expensive equipment or artificially introduce additional chemical or biologically active components into the system that can disrupt the ecological balance. It is enough to simply pass contaminated water through a filter or a suspension of boron nitride nanoparticles. The sorbent created by the researchers on the basis of hexagonal boron nitride is able to effectively purify antibiotic wastewater. In their study, NUST MISIS staff selected three types of antibiotics, which are among the most common pollutants: ciprofloxacin, tetracycline and bicillin. In the future, scientists plan to increase the sorption capacity of nanoparticles by applying a polymer and depositing metal ions, as well as expand the range of antibiotics under study.

Magnetic tunnel junction based on semi-metallic Geisler alloy/MoS2

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Magnetic tunnel junction based on semi-metallic Geisler alloy/MoS2
The article was published in ACS Applied Materials & Interfaces. Despite significant progress in recent decades, ultrathin oxide (MgO and Al2O3) spacers serving as tunnel barriers did not provide sufficient magnetoresistance (MR) in the vertical spin valve. Recently, two-dimensional materials have been considered as alternative spacers, demonstrating an extremely wide variety of electronic and structural properties. Graphene and h-BN have been considered as low resistance barriers for a vertical spin valve. In addition, the use of transition metal dichalcogenides (DPM) can significantly expand the variety of electronic properties and adjust the efficiency of magnetic transitions. In addition to the proper selection of 2D spacers, the search for an ideal source of spin-polarized electrons is of great importance. For this purpose, semi-metallic materials have been considered for several decades, including Geisler alloys such as Co2FeGe1/2Ga1/2, Co2MnSi, CoFeMnSi, Co2FeAl1/2Si1/2 and others. In this paper, a new magnetic tunnel junction based on electrodes made of Co2FeGe1/2Ga1/2 Geisler alloy and MoS2 spacer is proposed and theoretically investigated as a promising element for spintronics devices. The electronic and magnetic properties of the MoS2/CFGG interface have been studied using the DFT method for both FeGeGa and Co-termination of the CFGG surface. Stable ferromagnetism has been demonstrated over the entire thickness of the CFGG film. It is shown that spin polarization is suppressed in several outer atomic layers of CFGG due to interphase interactions and is rapidly restored within four atomic layers (up to 5 Å). Next, the spin-dependent ballistic transport of the CFGG/MoS2/CFGG magnetic tunnel junction is studied within the framework of the nonequilibrium formalism of the Green function for MoS2 spacers ranging from monolayer to four-layer films. In the case of a zero offset, the magnetoresistance values are in the range of 10^4-10^5%. Vol-ampere characteristics were also obtained, demonstrating the preservation of large values of MR at a bias voltage. Along with the latest achievements in the synthesis of graphene/CFGG heterostructure, this work supports further experimental and theoretical studies of semi-metallic magnetic transitions based on Geisler alloy with high efficiency in spintronics.

Diamane oxide. A two-dimensional film with a mixed coating and a variety of electronic properties

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Diamane oxide. A two-dimensional film with a mixed coating and a variety of electronic properties
The article is published in J. Phys. Chem. Lett. The possibility of light oxidation of sp2-hybridized carbon gives access to graphene oxide, one of the oldest and most studied graphene derivatives. Relatively inexpensive and widely available, GO is an attractive material for various applications in the field of sensors, energy storage, two-dimensional electronics and optoelectronics, photocatalysis and memristors, etc. Graphene oxide is a monolayer material, the further development of which can be devoted to the study of a thicker structure, such as bilayer graphene oxide. Hydrogenation or fluorination of bilayer graphene results in barrier-free bonding of the layers into an sp3-hybridized structure called diamane. The effect of the chemically induced transition predicted by us has been repeatedly confirmed in the experiment. It is important to note that, despite the successful synthesis of diamane by hydrogenation and fluorination, in most studies, graphene binding is associated with the deposition of oxide groups on its surface. Unlike hydrogenated and fluorinated diamane, the structure of oxidized diamane has not yet been studied in detail. There are only a limited number of papers in which relatively simple models are proposed. This is an obstacle to further analysis and interpretation of experimental data. The main problem is that graphene oxide (like diamane oxide) can be considered as a two-dimensional solid solution of various functional groups statistically distributed on the graphene surface. This is probably true for diamane oxide, therefore, the description of its structure requires considering it as a solid solution of various functional groups, as we proposed for graphene oxide. In the presented work, we tried to fill this gap and find out the details of the formation of diamane oxide, as well as its properties. We studied the idea that oxygen-containing groups are able to disrupt the π system and completely cover the outer surface of multilayer graphene, changing the hybridization of carbon atoms from sp2 to sp3. First, we found energetically advantageous structures of diamonds with a full surface coating of H, -OH or peroxide functional groups. Then we identified the thermodynamic stability range depending on the external pressure and chemical environment, determined by the choice of the precursor. In particular, we found that the commonly used oxygen source, H2O, requires the application of pressure to form stable oxidized diamane, which is in full accordance with experimental data. Next, we studied the possibility of regulating the electronic properties in energetically advantageous diamane films. We have shown that, depending on the concentration of OH groups on the surface, the band gap of diamane oxide can vary from 4.6 eV to 6.5 eV, and the effective mass varies from 1.1 m0 to 0.6 m0. For the two most representative films, namely H-diamane and OH-diamane, we studied how their electronic states change depending on the thickness of the film. We have shown that double-layered diamane behaves like a homogeneous semiconductor, while thicker films with more than 5 layers include surface and bulk regions with different conductivity properties.

The role of structural defects in the growth of two-dimensional diamond from graphene

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The role of structural defects in the growth of two-dimensional diamond from graphene
The work was published in the journal Nanomaterials. The synthesis of two-dimensional diamond is a daunting task, because unlike graphene and many other two-dimensional materials, diamane cannot be split from a crystal. Moreover, thermodynamic analysis shows that a diamond film of several layers without a stabilizing layer is unstable and decays into multilayer graphene, since the surface energy of diamond is higher than that of graphite. This conclusion is confirmed by an experiment in which graphene was subjected to high pressures in a diamond chamber. It was found that the pressure of diamond formation in multilayer graphene was much higher than in diamond, while the formed diamond films were unstable after pressure was removed. The most promising way to obtain a two-dimensional diamond is to use graphene as a precursor, on which third-party atoms (for example, hydrogen) are deposited. In this case, the thermodynamic stability of the material completely changes, the previously unstable diamond film becomes energetically advantageous, and the graphene layers tend to connect to each other. Despite a number of encouraging experimental results confirming such predictions, the issue of diamane synthesis is far from being resolved. Indeed, the nucleation of diamane in graphene is hindered by the high stability of the graphene π system, which resists the addition of new atoms. As a result, only two graphene layers can be relatively easily connected, and only if hydrogen plasma is used as a hydrogen source. In the case of using H2, a significant nucleation barrier can be expected to appear, which can only be overcome by high pressure and temperature. However, the actual graphene structure contains structural defects that can be used as nucleation centers, which may allow the synthesis of diamane under less harsh conditions. In the present paper, we have studied this effect in detail. To do this, we studied some of the most common structural defects in graphene and identified their effect on diamond nucleation. We found that the type and concentration of structural defects can sufficiently influence the initial and, most importantly, the subsequent stages of diamond nucleation. At the same time, the effect of defects on the strength of the C-H bond disappears already at the second coordination sphere. We have shown that the agglomeration of vacancies (which can be produced by low-energy ion irradiation) can sufficiently expand the reaction region, which disappears the nucleation barrier for the first stages of nucleation. The effect of Stone-Wales defects is less, but still contributes to the hydrogenation and bonding of graphene layers. We show that a 1D defect (dislocation) not only promotes diamond formation, but can also lead to the appearance of a 2D diamond consisting of chemically bonded grains of different crystallographic orientations. Therefore, polycrystalline graphene, usually observed in experiments, can become the basis for specific polycrystals of 2D diamond containing various surfaces. Even hexagonal and cubic 2D diamonds can coexist together in a single film with a grain boundary energy comparable to similar values for other two-dimensional carbon structures.

The edges are in a two-layer h-BN. Features of the atomic structure

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The article was published in Nanoscale (2022). The surface has always been of particular interest due to the wide variability of its structure and the presence of unusual properties. On the other hand, the "surface of the surface" - the edge of the nanostructure may be equally important and introduce new phenomena. The exact formation of edges on two-dimensional materials with a certain crystallographic orientation is a difficult task and requires precise knowledge of their chemical properties. In some cases, the edge shows a very specific structure. For example, the edges of multilayer graphene tend to connect to each other. The case of double-layered graphene has been studied in detail, and it has been shown that the connection of the edges does not even require overcoming any barrier, and therefore a hollow sp2-hybridized graphene structure is spontaneously formed. In our previous work, it was shown that the structure of the closed edges of bigrafen is actually strictly defined and can be represented as a curved interface between disoriented (in the general case) graphene grains. Understanding the edge structure is also important for the case of the formation of holes in a two-dimensional structure, since it is an attractive object for changing the properties of the material. For single-layer graphene, many studies have been conducted on holes for DNA sequencing, gas sensing, ion and molecular filtration (in particular, water desalination), molecular transport, etc. Several similar studies have also been conducted with hexagonal boron nitride (h-BN) and molybdenum disulfide (MoS2). The variety of hole shapes and types of passivation of their edges does not allow for systematic experimental studies. Research usually focuses on performance tests without information about edge configuration and chemical stability, which can significantly affect performance. The carbon double, boron nitride, is less studied in this regard, although it seems promising to create holes not in bigraphene, but in the double-layered h-BN. Indeed, the strong tendency of layers towards AA' packaging makes it possible to be sure that the two-layer structure will be predetermined. However, it remains completely unclear which edges of the multilayer h-BN will tend to close and what the final structure will be. The structure of the edges of multilayer h-BN is usually unknown, whereas from the general logic one can expect a similar self-passivation effect due to the close values of bending stiffness and edge energy. The presented work is devoted to the study of the edges of two-layer h-BN. It is shown that the edges tend to join regardless of the cut. A defect-free connection can be expected only in the case of a zigzag edge, in other cases a number of tetragonal and octagonal defects are formed. This result was obtained by drawing an analogy between the edge of a two-layer h-BN and the interface of a monolayer h-BN (see figure). Information about the structure and energy of the closed edges made it possible to predict the shape of the holes in h-BN, which is consistent with experimental data. Finally, it is shown that closed edges do not create states in the band gap, thereby not changing the dielectric of h-BN.

Semiconductor channels in carbon nanotubes by thermomechanical chirality modification

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The work was published in the journal Science 374, 1616-1620 (2021) This work was done in collaboration with a number of foreign institutes, the main experiment in which was conducted at NIMS (Tsukuba, Japan), Prof. D.M.Tang. Experimental measurements of chirality during stretching of carbon nanotubes (CNTs) and heating to 2000 K showed that plastic deformation occurred in its central section, while a clear tendency to increase the chiral angle was observed. Interestingly, this contradicted the previous theoretical model describing plastic deformation through the movement of dislocation nuclei (defects 5/7, adjacent pentagon and heptagon) arising from high deformations in CNTs from the Stone-Wales defect, and predicting a gradual decrease in the chiral angle. Experimental conditions allowed us to assume that due to the extremely slow elongation of the heated nanotube, the formation of Stone-Wales defects (and their further transformation into dislocation nuclei 5/7) cannot be the main reason for the change in chirality, since the process of formation of such defects under these conditions is reversible. To solve this problem, we proposed and theoretically described a new mechanism according to which dislocations are formed as a result of evaporation of carbon dimers (C2) and the associated formation of defects 5/8/5. This defect can split into dislocations 5/7, both as a result of the rotation of bonds, and due to further evaporation of carbon (Fig. (d,e)). The calculated defect formation energy of 5/8/5, depending on the chirality angles, using density functional theory methods shows that in CNTs with a small chiral angle, it is energetically more advantageous for dislocations with the Burgers vector (1.0) to appear, which increase the chiral angle as a result of movement through the structure. We also calculated the ratio of the probabilities of dislocation formation (1.0) and (0.1) to predict the chirality trend according to our model. The result (Fig. (f)) made it possible to accurately describe experimental observations and explain the nature of the mechanism of plastic deformation of nanotubes at high temperatures and slow stretching. Thus, we have studied the method of local chirality change, which allows us to implement metal-semiconductor-metal contact in single-walled carbon nanotubes, that is, to create an intramolecular transistor based on nanotubes.

Experimental and numerical study of nanostructured materials based on graphene and its compounds

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The project is dedicated to the development of new means of obtaining nanostructured materials and the study of new graphene-based materials with electrical, mechanical and optical properties promising for various applications. The study of the created materials will be carried out not only experimentally, but also using numerical modeling methods. For the successful development of graphene electronics, it is extremely important to understand the physics of the influence of various structural features of a material on its electrical and optical properties. Such features may include edges, interfaces between regions with different lattice parameters, and mechanical stresses.

Investigation of new classes of nanomaterials with an unusual structure: films of monoatomic thickness based on d-metals and quasi-one-dimensional van der Waals nanowires and nanofilms of the composition M2X3 and M2X3Y8

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The project will study the stability and properties of a new class of nanomaterials with a special atomic structure determined by low dimensionality. The novelty of the project is primarily due to the choice of research objects, the systematic study and description of which (despite their prospects) has not yet been carried out. We propose to investigate for the first time two families of materials, each of which has its own attractive properties: films of monoatomic thickness based on a number of metals and quasi-one-dimensional structures of binary M2X3 and ternary M2X3Y8 compositions. The project will carry out a comprehensive theoretical study of the structure and physico-chemical properties of such objects, as well as predict the mechanisms of their production and identify potential applications. The obtained data will significantly expand the fundamental knowledge about low-dimensional nanomaterials, will allow a comprehensive description of their potential properties, and the results of the project will become the basis for further controlled synthesis of nanostructures with the necessary composition and properties, which will undoubtedly arouse the interest of the scientific community in this problem and can take the development of the field of synthesis of low-dimensional materials to a new level.

Chemically induced phase transition in low-dimensional structures

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Controlled change in the structure of nanomaterials at the atomic level is the most important task of modern materials science. The influence of the surface is expressed in the need to take into account the size of nanostructures when describing their stability. This problem is especially clearly manifested in the study of the phase transformation of nanomaterials, when their energy begins to depend not only on external conditions, but also on the contribution of surface effects. For example, the classical carbon Bandy phase diagram changes as the thickness of the carbon film decreases, the pressure of the graphite-diamond phase transition increases, which reflects an increase in the instability of the diamond as its size decreases. Upon reaching atomic thickness, diamond films should exhibit a number of extremely attractive physical properties, but their synthesis requires fundamentally different approaches. Two ways of synthesizing nanomaterials seem natural for today's science: top-down and bottom-up methods. The top-down method, when the macroscopic material is separated to the required nanostructure, was not considered, since it is probably impossible to obtain diamond films of nanometer thickness by separating a diamond crystal. The bottom-up method (the necessary nanostructure is synthesized from smaller nanostructures) seems to be the most attractive for this case, although it certainly requires overcoming a number of non-trivial scientific problems. The traditional method of chemical deposition from the gas phase is not applicable to solving the problem of obtaining diamonds of atomic thickness due to the high growth rate of diamond layers and their heterogeneity at the atomic level. Therefore, in this paper, we will consider another option for producing diamond films, when the starting material is not steam, but a two-layer graphene film. The formation of diamond films occurs through a controlled chemical reaction of two graphene sheets with third–party atoms, mainly hydrogen or fluorine. We will test this method experimentally, and theoretically we will study in detail the mechanism of transformation of graphene layers not only in the case of bilayer graphene, but also other structures based on weakly bonded layers – double-layered carbon nanotubes and related nanomaterials.

Publications and patents

Lab address

Ленинский пр 4, каб. Б-435а
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