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The laboratory was founded by Prof. D.A.Bochvar (1903-1990) in 1967 on the base of the quantum chemistry group, which was organised in INEOS as early as 1956 due to the initiative of Academician A.N.Nesmeyanov.
In 1987, the laboratory was renamed to the Laboratory of computational chemistry. In 1989, the quantum chemistry group was separated from the laboratory as an independent research unit, and in 1994, this group again received status of laboratory.
1. Formation probabilities of stable complexes between fullerenes and some of their derivatives (б60, б70, б60X5, б60е6, б60е10, б70е10, б70X5; X = H, Cl, Br, C6H5) and M, MCp, MBz (M - metal atom) fragments with h5- and h6-coordination, have been theoretically analysed. It has been demonstrated that h5-complexes formed by б60е5 fullerene derivatives with functional group X attached to the carbon atoms, adjacent to the same 5-membered ring, should be thermodynamically stable (first representatives of such cyclopentadienyl complexes were prepared in 1996 in Japan).
Possibility of existence of giant oblate-shaped polyhedral carbon clusters composed of interlinked extended fragments of graphite layers, has been demonstrated.
Existence of dumpbell shaped carbon clusters has been theoretically predicted for the first time. A new class of filamentary carbon and silicon clusters build up of sp2- and sp3-hybridised atoms, has been described. Electronic structure of bamboo-like quasi one-dimensional carbon clusters, have been calculated. As it has been established, electronic spectra of such macromolecules should contain minizones.
A method for calculation of Tamm's energy levels in spectra of semiinfinitive carbo-tubulenes, which accounts for terminal group structure, has been suggested.
Atomic and electronic structure calculations for polyhedral clusters X12Y12 and X16Y16 (X=B, Al, Si; Y=N, P, C) composed of 4- and 6-membered rings with alternating arrangement of X and Y atoms, have been performed.
For б45 and SiC44 taken as examples, the instability of "filled" structures for compounds with such a stoichiometry has been shown. As it has been established, in contrast to Si45, these molecules convert into endohedral clusters of the X@C44 type upon energy minimisation.
Geometry and electronic structure of tubular carbon nitride forming quasi one-dimensional superlattices, has been theoretically simulated for the first time. Electron spectra of several isomeric [B6N6C12]n nanotubes, which have 6-fold symmetry axes, have been calculated in the topological and valence approximations. It has been found that introduction of cyclic carbon fragments between the dielectric boron nitride rings leads to a substantial decrease in the forbidden zone width as compared to that of pure boron nitride and to the appearance of minizones in their electron spectra. Principle possibility of existence of fullerene C60 complexes 12h5-p-б60MCp, M=Fe, Ru, Os, was proved. It was shown that butadiene and allyl tiype derivatives of fullerene C60 can produce stable complexes with transition metals. Modeling of structure and electron properties of new allotropic carbon forms on base fullerene C20 and cubic cluster C8 was carried out by DFT. It was shown theoretical that stable carbon clusters can consist of fullerenes and fragments of carbine molecules.
2. Atomic and electronic structure of complexes of tri- and pentameric mercury-containing macrocycles [(C2X2Hg)3, (ю-C6X4Hg)3; X = H,F; (CX2Hg)5; X = F, CF3] with halogenide anions е- have been analysed theoretically. Various structural types, viz. half-sandwich, sandwich, and propeller, have been studied. Applicability of a qualitative description of electronic structure for the above complexes within the generalised chemical bonds formalism suggested earlier for transition metal -complexes, has been demonstrated. Similarities and differences in the character of bonding between the respective cycle and central atom depending on the type of the latter (transition metal or halogenide anion), have been analysed. In particular, it has been shown that sandwich complexes based on halogenide anions should have non-symmetric structure, in which two macrocycles are at different distances from the central atom and thus they have to be considered as half-sandwiches [L - X]- solvated by the second macrocycle L (in collaboration with the Lab. of Prof. V.B.Shur, INEOS). Similar studies have been undertaken for complexes of the macrocycle (HgC6F4)3 with such anions as S2-, H-, Cp-, and ТH4-. In particular, the semi-empirical AM1 quantum chemistry method has been applied in order to investigate the structure and the nature of chemical bonds in the complex of the above trimeric perfluoro-o-phenylmercury with ТH4- anion with compositions 1:1 (I), 2:1 (II), and 1:2 (III) detected earlier by IR and NMR. It has been shown that the complexes I and II have half-sandwich and bipyramidal structures, respectively. Furthermore, chemical bonding therein is, in general, similar to that in the respective complexes with halogenide anions, since borohydride anion in this case can be represented as a single virtual atom. This virtual atom has 8 valence orbitals (as compared to 4 in the case of halogenide anion) thus it can form true sandwich complexes. Meanwhile, the complex III has two stable sandwich-type isomers, the most stable one of the two possesses unusual geometry: it is a sandwich of the C2v symmetry with mercury atoms differently coordinated to hydrogen atoms of the BH4- anion. (In collaboration with the Labs. of Profs. V.B.Shur, D.N.Kravtsov, and A.S.Peregudov).
3. As a development of theory of the saturated hydrocarbons activation by aprotonic electrophilic complexes, a quantum chemical simulation of atomic and electronic structure of superelectrophiles generated from polychalogenmethanes in protic and aprotic acids as well as from mBr2*nAlBr3 systems, has been perfomed.
There have been studied the potential energy surface (PES) profiles for the following systems: CF4*nAlF3 and CBr4*nAlBr3 (AM1), CCl4*nAlCl3 and CCl3+*AlCl3 (both AM1 and ab initio), trichalogenomethyl cations and their protonated derivatives (ab initio and DFT). It has been shown that ionic (cationic and dicationic) complexes can be formed in CX4*nAlX3 (X = Cl,Br, I) systems. In such complexes (as well as in free cations and dications), carbon atoms are negatively charged and positive charge is localised on terminal halogen atoms. Thus, these complexes can be considered as halogenium rather than halogenonium salts, which have dicoordinated halogen atoms. The study conducted allowed us to conclude that the key role in reactions of бе4*nAlX3 with alkanes is played by a new type of electrophiles, viz. halogenium cationic complexes. In such complexes, the mono-coordinated halogenium atom, which carries the positive charge of the CX3+ cation, is solvated by negatively charged halogen atoms of AlX4- anion via bi- or tridentate coordination.
A series of mBr2*nAlBr3 systems has been studied using MNDO/PM3. A probable existence of superelectrophile complexes with bidentate coordination of AlBr4- to the bromium atom, which carries the maximum positive charge within the cluster (up to 1.45 at. units), has been demonstrated. A case theoretical study of alkanes interaction with superelectrophiles generated in the [Br2*AlBr3] system has been performed for methane and respective model electrophiles. Potential energy surfaces (PES) of the [Br+ + CH4] (I) and [Br+ + AlBr4- + CH4] (II) interacting systems have been studied using the MNDO/PM3 and ab initio MO LCAO SCF/6-31G methods. As it has been established in both of the systems studied, the complex formation proceeds without activation barrier as a result of the electrophile attack at one of methane hydrogen atoms.
Therefore, we have found the third route of alkane interactions with electrophile reagents (in addition to the classical scheme of Olah, which implies cation attack at the б-Э bond and Shreiner's scheme postulating electrophile attack at the methane carbon atom).
The results obtained support that these third route (electrophile attack at hydrogen atoms) is the preferable one in the case of C-H bond activation in alkanes by electrophiles generated in the [Br2*AlBr3] system. (In collaboration with the group of Prof. I.S.Ahrem, INEOS).
4. A new method of isomorphous graphs characterisation has been suggested. It is based on utilisation of the graph's eigenvectors and corresponding projection operators. This method can be used for canonical numeration of atoms in molecules as well as for coding of structures of chemical compounds.
A general approach to invariant molecular graph and their similarity construction has been developed.
A quantum chemistry interpretation of the Randich's index has been suggested.
A new method for obtaining lower estimates for molecular hydrogen ion potential energy curve has been developed.
Relations (inequations), which link total energy of carbon clusters and isostructural boron carbonitride clusters, have been formulated.
5. It was proved by quantum chemical methods possibility of existence of news diamante-similar allotropic forms of C, Si and Ge formed of dodecahedral and cubic clusters X20 and X8, X=C, Si, Ge, рnd also cubic crystalline structures [C20]n ё doped by atoms M = Na, Ca, Sr, Sc, Y. It was shown that structures [MC20]n at M = Ca, Sr must possess good conducting properties.
1. Elena G. Gal’pern, Alexsei R. Sabirov, Ivan V. Stankevich, Derivatives C21H12R6 of sumanene C21H12 as bowl-shaped precursors of derivatives R6C60 fullerene C60 (R = —, H, Hal, CN, Fullerenes, nanotubes, and crbon nahostructures. 2008, V.16, 538-541
2. V.I.Sokolov], R.G.Gasanov, Lai Yoong Goh, Zhiqiang Weng, A.L.Chistyakov, I.V. Stankevich, (Cyclopentadienyl)chromiumtricarbonyl dimers as a source of metal-centered free-radicals to form stable 2-bonded spin-adducts with fullerenes, JOMC, 690(2005) 2333-2338.
3. M.I. Skvortsova, I.V. Stankevich, Eigenvectors of weighted graphs: a supplement to Sachs’ theorem, J. Mol.Str. (Theochem) 719(2005) 213-223.
4. N.А. Ogorodnikova, On invariance of the Mulliken substituent-induced charge changes in quantum-chemical calculations of different levels. J.Mol.Struct. (Theochem) 894 (2009) 41-49
5. E.G. Gal’pern , I.V.Stankevich Fullerenes, Nanotubes, and carbon nanostructures, 2010 v.16, 450