We use cookies.
By using the site, you agree to our Privacy Policy.

Laboratory of Theoretical Modeling of Polyfunctional Materials

Invited researcher Alexandr Ivanovich Boldyrev
Contract number
14.Y26.31.0016
Time span of the project
2017-2019

As of 08.06.2020

20
Number of staff members
106
scientific publications
General information

Name of the project: Theoretical modeling of polyfunctional elemento-organic and coordination compounds and materials based on them with adjustable optical, electric and magnetic qualities.

Strategy for Scientific and Technological Development Priority Level: а


Goals and objectives

Research directions: Research of new allotropic forms of boron, carbon, aluminum and silicon

Project objective: Organizing a modern, well-equipped laboratory of quantum chemistry at the Southern Federal University that will serve as the basis for conducing researchers in quantum chemistry and molecular design of one-, two- or three-dimensional molecular systems with adjustable electric and magnetic qualities for uses in molecular electronics, spintronics and various fields of technologies


The practical value of the study

1. By means of computer modeling with application of periodic boundary conditions we have researched the geometrical and electron structure of a new allotrope of aluminium – crystalline supertetrahedral aluminium produced on the basis of the diamond lattice in which carbon atoms are replaced by Al4 tetrahedrons. Calculations of the electron zone structure of supertetrahedral aluminium have shown the capability of the studied material to demonstrate a decent electric con decent electric conductivity and plasticity which allows to classify it as a semimetal. The predicted photon spectrum testifies to the dynamic stability of this supertetrahedral aluminium structure. Supertetrahedral aluminium, according to the computations, has the density of 0.61 g/cm3 winch is significantly lower than the density of water and the density of pure crystalline aluminium that is 2.7 g/cm3. The calculated values of the Hooke's constant and the shear modulus of this material indicate its high plasticity. The paper describing these results has generated widespread interest in the world.

2. We have studied a new form of supertetrahedral aluminium based on the diamond lattice in which couples of adjacent carbon           atoms are replaced by a fragment of tetrahedral aluminium connected with a covalent bond to a Х Al4-X (X=B, C, Al, Si) atom. The cF-Al4C and cF-Al4Si crystal structures are the metastable phases of these substances, they are indirect-band-gap semiconductors, possess sufficiently high hardness and plasticity. The cF-Al4B and cF-Al4Al crystal structures are dynamically unstable and are of no interest in the practical sense. The results have been published.

3. Using quantum chemical computations in the rigid–body approximation we have predicted a new allotropic form of gallium constructed on the basis of the diamond grid in which each carbon atom is replaced by a Ga4 tetrahedron. The new material is a semiconductor, it has a low density (1.74 g/cm3) as well as a high plasticity, its melting temperature is 273 К. The material produced on the basis of this allotropic form can find applications as a low-density metal. The results have been published.

4. Using quantum chemical computations in the rigid–body approximation we have modelled a ferromagnetic supertetrahedral two-dimenional boron material. The results of computation of the phonon spectrum and the molecular dynamics have demonstrated that the monolayer of 2D-B6 is dynamically and thermally stable. Moreover, it possesses significant magnetic properties and has a metal electron structure. The predicted material is a second example of a magnetic 2D sheet and a first example of a ferromagnetic metallic 2D sheet formed from pure boron. Therefore, this material is of high interest for the modern materials science and its thermal and mechanical stability promises a wide range of applications. The results have been published.

5. Using computer modeling with application of periodic boundary conditions we have demonstrated that the new material difluorophosphorane should have a flat structure in which fluorine atoms are situated above and below the plane of phosphorus atoms. This structure is dynamically stable and is a semiconductor. It is promising for usage in nanoelectronics. The results have been published. 

6. Using quantum chemistry methods we have modelled a number of nonmetallic two-dimensional materials with uncoupled p electrons among which we have found a new two-dimensional metal with the SiN composition displaying ferromagnetic properties. Computations of the phonon spectrum and the molecular dynamics have shown that the 2D-SiN monolayer is dynamically and thermally stable which makes it a potential candidate for experimental implementation. The results have been published.

7. We have conducted quantum chemical computations of extended nonmetallic chains with the general formula PnX3n + 2 (X = F, Cl) and infinite –(PX3–PX3)– chains. It has been demonstrated that all the highly symmetrical PnX3n + 2 (n = 2–9) structures meet the minimum energy requirement. At the same time, higher stability is shown by structures in which the P–X bond is in an equatorial position. Rotation around the P–P bind for fluorine derivatives is a low-barrier process, in the case of chlorine derivatives it is accompanied with molecular dissociation. Computations with application of periodic boundary conditions modelling the –(PX3–PX3)– infinite linear chain have shown that both researched systems are dynamically stable and are wide-band semiconductors with a direct junction. The results have been published.

8. From the results of computations we have proposed a new type of catalyst, MgO, with periodic defects on the surface. This catalyst demonstrates high catalytic activity. It has been shown that magnesium oxide with periodic defects on the surface has doubly occupied multicentre bonds inside each defect in which there is no oxygen atom. It turned out that these structures are stable at temperatures of up to 1500 К which opens a possibility for its application even under extreme conditions. In this work we have reviewed both multiple and rare defects that are potential catalysts with a single defect. The results have been published.

9. Using the density-functional theory we have studied the structure and properties of binuclear coordination compounds of transition metals with o-quinone ligands based on polyacenes. It has been demonstrated that an increased number of condensed rings leads to stabilisation of the biradicaloid state of acenes and a switch of the nature of the exchange interactions between semiquinone forms of redox-active fragments from antiferromagnetic to ferromagnetic. The proposed cobalt(II) diketonate with acenes functionalised by quinone fragments are able to undergo one- and two-stage spin transitions induced by intramolecular electron transfers between metal ions and the ligand system. The unusual magnetic properties predicted by the computations and caused by migration of paramagnetic centres allows to view these complexes as promising candidates for developing molecular electronics and spintronics devices. The results have been published.

10. Using the density-functional theory we have studied a number of new magnetically active binuclear cobalt diketonates with mixed ligands that contain acene linkers. The results have been published.

11. The results of computer modelling have shown the viability of the proposed cobalt(II) diketonate adducts with polycyclic triangulene hydrocarbons functionalised by o-benzoquinone groups. By rational selection off substitutes in terminal ligands we have determined molecules that are able to undergo thermally induced valence tautomeric regrouping. The expected transformations will be accompanied with a change of the magnetic properties within a wide range which allows to view the studied mixed-ligand complexes as molecular switches and spin qubits. Introduction of heteroatoms into the polycyclic triangulene fragment leads to an increase of the difference in energies between the main (low-spin) and high-spin states of mononuclear metal complexes which allows us to expect spin transitions only in complexes with cobalt hexafluoroacetylacetonates. The results have been published.

12. Using the density-functional theory we have studied the structures and stability of a new family of metal-carbonyl Cr(CO)5, Fe(CO)4, Ni(CO)3, Ti(CO)4, Ni(CO)2,, cyclooctatetraene and cyclodecapentaene derivatives. All the derivatives of cyclooctatetraene except for the Ti(CO)4 derivative have a flat structure and are characterised by expressed antiaromaticity of the central cycle. In the case of cyclopentadecaene complexes flat structures are formed only for the Fe(CO)4 and Ni(CO)3 derivatives. Stabilisation of non-standard flat forms is caused by sterically induced flattening of the central cycle and its π-interactions with metal-carbonyl fragments. The results have been published.

13. With help of quantum chemical modelling of the structure and magnetic qualities of a series of neutral triangulene polycyclic aromatic hydrocarbons functionalised by various radical groups we have found a dependence of the nature and strength of volume interactions between the paramgnetic centres on the size of the triangulene fragment, presence of heteroatoms in it, the type of radical replacements and their spatial locations. We have proposed molecules that have a high-spin main electron state and displaying ferromagnetic volume interactions that allow to promote such systems as promising construction blocks for organic spintronics devices. The results have been published.

14. We have conducted a quantum chemical study of the possibility of stabilisation of the N3P3 aromatic molecule with a flat hexagonal structure. This isomer is characterised by thermodynamic instability in respect of dissociation into a van der Waals complex of the distorted NP3 tetrahedron and the N2 molecule but is kinetically stable, characterised by high energy barriers of possible isomerisations which allow to expect its existence under thermal conditions. The results have been published.

15. We have published an overview devoted to the concept of σ-aromaticity and σ-antiaromaticity. Our researchers have investigated examples of clusters, molecules and solid bodies in which this concept helps to understand chemical bonding. It has been demonstrated that for σ-aromaticity and σ-antiaromaticity principles of bonding are similar to those for π-aromaticity and π-antiaromaticity.

16. For the first time we have synthetically produced and completely characterised the new [K([2.2.2]crypt)]4[In8Bi13] complex that consists of two clusters: [Bi@In8Bi12]3- Th-symmetry and [Bi@In8Bi12]5- Cs-symmetry. These are the largest In/Bi clusters of all the currently known ones. Using quantum chemical computations (AdNDP, ELF, NICS) we have demonstrated that spherical aromaticity is implemented in the clusters. This explains high symmetricity, stability and magnetic properties of these compounds. The results have been published.

Education and career development:

  • We have conducted an internship for students, postgraduates and employees in two courses: «Advanced administration of Linux Enterprise Server 12», «Vizualzation of data using Microsoft Excel 2013 and Microsoft PowerPoint 2013».
  • The Laboratory have created an education module «Modern state of chemical bonding theory» that are a part of the «Methods of synthesis of materials» major of the «Polyfunctional materials» master.
  • Employees of the laboratory have completed training on supercomputer technologies at the «Quantum informatics» course organised by the Moscow State University.
  • Employees have completed training at the «Theoretical and practical problems of conducting quantum chemical research using Gaussian 16» provided by Gaussian, Inc. at the University of Ulm (Germany).

Hide Show full
Getmanskii I. V., Koval V. V., Minyaev R. M., Boldyrev A. I., Minkin V. I
Supertetrahedral aluminum − a new allotropic ultralight crystalline form of aluminum // J. Phys. Chem. C. – 2017. – Vol. 121. – P. 22187−22190. Quartile: Q1, Impact Factor2018: 4.309.
Popov I. A., Starikova A. A., Steglenko D. V., Boldyrev A. I.
Usefulness of the σ-aromaticity and σ-antiaromaticity concepts for clusters and solid-state compounds // Chem. Eur. J. – 2018. – Vol. 24. – P. 292– 305. Quartile: Q1, Impact Factor2018: 5.16.
Starikova A. A., Boldyreva N. M., Minyaev R. M., Boldyrev A. I., Minkin V. I.
Computational assessment of an elusive aromatic N3P3 molecule // ASC Omega. − 2018. – Vol. 3. − № 1. – P. 286−291. Quartile: Q2, Impact Factor2018: 2.584.
Steglenko D. V., Minyaev R. M., Minkin V. I., Boldyrev A. I.
Difluorophosphorane – flattened phosphorene through difluorination // J. Phys. Chem. Lett. – 2018. – Vol. 9. – № 24. – P. 6963−6966. Quartile: Q1, Impact Factor2018: 7.329.
Minkin V. I., Starikov A. G., Starikova A. A., Minyaev R. M., Boldyrev A. I.
The structurally variable network of spin couplings and migrating paramagnetic centers in the binuclear o-quinone CoII complexes with the biradical acene linkers: a computational DFT study // Dalton Trans. – 2018. – Vol. 47. – № 44. – P. 15948–15956. Quartile: Q1, Impact Factor2018: 4.052.
Gribanova T. N., Minyaev R. M., Minkin V. I., Boldyrev A. I.
Metalcarbonyl analogues of annealed cyclooctatetraene and cyclodecapentaene derivatives with a planar core cycle: a quantum chemical study // Phys. Chem. Chem. Phys. – 2018. – Vol. 20. – P. 27830–27837. Quartile: Q1, Impact Factor2018: 3.567.
Getmanskii I. V., Koval V. V., Boldyrev A. I., Minyaev R. M., Minkin V. I.
Computationally designed crystal structures of the supertetrahedral Al4X (X=B, C, Al, Si) solids // J. Phys. Chem. A. – 2019. – Vol. 123. – № 1. – P. 267–271. Quartile: Q2, Impact Factor2018: 2.641.
Getmanskii I. V., Koval V. V., Boldyrev A. I., Minyaev R. M., Minkin V. I.
Molecular dynamic study of a new metastable allotropic crystalline form of gallium- supertetrahedral gallium // J. Comput. Chem. –2019. – Vol. 40. – № 20. – P. 1861–1865. Quartile: Q2, Impact Factor2018: 3.224.
Tkachenko N. V., Steglenko D. V., Fedik N. S., Boldyreva N. M., Minyaev R. M., Minkin V. I., Boldyrev A. I.
Superoctahedral two-dimensional boron with peculiar magnetic properties // Phys. Chem. Chem. Phys. – 2019. – Vol. 21. – № 36. – P. 19764–19771. Quartile: Q1, Impact Factor2018: 3.567.
Tkachenko N. V., Zhang X.-W., Qiao L., Shu C.-C., Steglenko D. V., Muñoz-Castro A., Sun Zh.-M., Boldyrev A. I.
Spherical aromaticity of all-metal [Bi@In8Bi12]3-/5- clusters // Chem. Eur. J. – 2020. – Vol. 26. – № 9. – P. 2073-2079. Quartile: Q1, Impact Factor2018: 5.16.
Minkin V. I., Starikov A. G., Starikova A. A., Gapurenko O. A., Minyaev R. M., Boldyrev A. I.
Electronic structure and magnetic properties of the triangular nanographenes with radical substituents: a DFT study // Phys. Chem. Chem. Phys. – 2020. – Vol. 22. – № 3. – P. ‏1288-1298. Quartile: Q1, Impact Factor2018: 3.567.
Other laboratories and scientists
Hosting organization
Field of studies
City
Invited researcher
Time span of the project
International Research Laboratory «Non-valent Interaction in Materials Chemistry»

National Research Tomsk Polytechnic University

Chemistry

Tomsk

Resnati Giuseppе

Italy

2021-2023

Laboratory of Microwave Activation of Catalytic Processes

N.D.Zelinsky Institute of Organic Chemistry Russian Academu of Sciences

Chemistry

Moscow

Salmi Tapio Olavi

Finland

2021-2023

Spin Hyperpolarisation Laboratory

International Tomography Center Siberian Branch of Russian Academy of Sciences

Chemistry

Novosibirsk

Bodenhausen Geoffrey

France

2021-2023