?
Formation and decay of a triplet state of dipyrido[3,2-a:2′,3′-c]phenazine
Mendeleev Communications. 2020. Vol. 30. No. 3. P. 322-324.
Glebov E., Bakulina O. D., Shushakov A. A., Matveeva S. G., Pozdnyakov I., Grivin V., Plyusnin V., Vasilchenko D., Melnikov A., Chekalin S.
The photophysical and photochemial properties of dipyrido[3,2-a:2′,3′-c]phenazine (dppz) in acetonitrile have been investigated by laser flash photolysis and ultrafast pump-probe spectroscopy. The excitation of dppz to the first singlet excited state was followed by vibrational cooling with solvent relaxation for ∼3 ps and then intersystem crossing for ∼50 ps. Spectral and kinetic characteristics of the triplet excited state have been determined.
Glebov E., Pozdnyakov I., Semionova V. V. et al., Mendeleev Communications 2020 Vol. 30 No. 1 P. 61-63
Early processes in photochemistry of 2,3-bis(2,5-dimethylthiophen-3-yl)cyclopent-2-enone were explored using the ultrafast pump-probe spectroscopy. The photocyclization occurs from the antiparallel conformation of an open form on a time scale of 7 ps, while the parallel conformation exhibits an intersystem crossing within 130 ps. The mechanism and timescales were revealed as typical of other thiophene-containing diarylethenes. ...
Added: January 18, 2021
Glebov E., Matveeva S. G., Pozdnyakov I. et al., Photochemical and Photobiological Sciences 2020 Vol. 19 P. 1569-1579
The photochemistry of the OsIVCl62− complex in ethanol was studied by means of stationary photolysis, nanosecond laser flash photolysis, ultrafast pump–probe spectroscopy and quantum chemistry. The direction of the photochemical process was found to be wavelength-dependent. Irradiation in the region of the d–d and LMCT bands results in the photosolvation (with the wavelength-dependent quantum yield) and ...
Added: January 18, 2021
Shushakov A. A., Matveeva S. G., Pozdnyakov I. et al., Photochemical and Photobiological Sciences 2020 Vol. 19 P. 1222-1229
It is known that trans,cis,cis-[RuCl2(DMSO)2(H2O)2] (1a) complexes, which are formed upon dissolution of trans-[RuCl2(DMSO)4] in water, demonstrate light-induced cytotoxicity. The mechanistic study of 1a photochemistry has been performed using ultrafast pump–probe spectroscopy, laser flash photolysis and stationary photolysis. The first stage of 1a photochemistry is the photoexchange of a DMSO ligand to a water molecule; its quantum yield is wavelength-dependent (estimating ...
Added: January 18, 2021
Pozdnyakov I., Melnikov A. A., Šípoš R. et al., Chemical Physics Letters 2016 Vol. 660 P. 209-213
Transient absorption spectroscopy is used to study photophysical processes of 1:1 Fe(III) complexes with all four fluorosalicylic acid isomers (Fe-FSAs) in aqueous solutions. Excited states of Fe-FSAs decay to the ground electronic state with two time constants. The faster process is interpreted as internal conversion to the vibrationally hot electronic ground state and the slower ...
Added: October 31, 2018
Melnikov A., Pozdnyakov I., Chekalin S. et al., Mendeleev Communications 2020 Vol. 30 No. 4 P. 509-511
The time of ultrafast intersystem crossing for the PtIVBr62– complex in aqueous solution was measured by a fluorescence up-conversion technique. The corresponding time constant (140 ± 40 fs) is in agreement with that estimated from previous ultrafast transient absorption measurements and with the reported results of theoretical calculations. ...
Added: January 18, 2021
Olloqui-Sariego J. L., Zakharova G., Poloznikov A. et al., Electrochimica Acta 2020 Vol. 351 P. 136465
A major challenge in the design of electrochemical biodevices is to achieve fast rates of electron exchange between proteins and electrodes. In this work, we show that a significant increase in the direct electron transfer rate between a graphite electrode and Tobacco Peroxidase takes place when a surface exposed leucine, located in the vicinity of ...
Added: July 22, 2020
Можчиль Р. Н., Ionov A. M., Божко С. И. et al., Поверхность. Рентгеновские, синхротронные и нейтронные исследования 2023 № 1 С. 25-30
The features of the electronic and local atomic structure of erbium metalloporphyrins Er(acac)TPPBr8 and Er(acac)TPP and precursor tetraphenylporphyrins TPP and TPPBr8 are studied by X‑ray photoelectron spectroscopy and X-ray absorption spectroscopy. Using photoelectron spectroscopy, the structural parameters of the Er4 d, N1s, C1s, O1s, and Br3d core levels and the valence band are determined. The change in the electronic ...
Added: December 24, 2023
Darya Gurina, Ekaterina Odintsova, Krestyaninov M. A. et al., Journal of Molecular Liquids 2023 Vol. 390 No. A Article 122961
The paper presents a study of the behavior of room-temperature ionic liquids with different alkyl chain lengths and anion types in slit negatively charged carbon nanopores of various widths (1÷15 nm) using all-atom molecular dynamics simulations. The structure of the confined ionic liquids is investigated using number, mass, and charge density profiles and radial distribution ...
Added: August 31, 2023
Голосов Е. В., Алдошин С. М., Палий А. В. et al., Reviews and Advances in Chemistry 2021 Vol. 11 No. 3-4 P. 145-165
This article is a short overview of the problem of controllable magnetic spin communicationas an important ingredient of spintronics and molecular electronics. We discuss the problem of communicationof the two localized spins mediated by the mobile electron which is shared between twonon-magnetic sites coupled to the mobile spins. The model system which is assumed to ...
Added: October 10, 2022
Pavlova T., Eltsov K., Андрюшечкин Б. В. et al., Journal of Physical Chemistry C 2018 Vol. 122 No. 50 P. 28862-28867
Coadsorption of chlorine and oxygen on the Ag(111) surface has been studied with low-temperature scanning tunneling microscopy in combination with density functional theory calculations. Room-temperature adsorption of chlorine onto the Ag(111)-p(4 X 4)-O surface leads to the appearance of new bright objects located between protrusions of the 4 X 4 reconstruction. As chlorine adsorbs, objects form "rosettes" around corner holes. This configuration coincides with the configuration of the chlorine atoms in the Ag(111)-(3 X 3) Cl reconstruction structure. We conclude that the adsorption of chlorine on the Ag(111)-p(4 x 4)-O surface ...
Added: October 25, 2021
Nikita S. Komarov, Vladimir M. Shevlyuga, Loginov B. et al., Journal of Physical Chemistry C 2023 Vol. 127 No. 5 P. 2266-2273
Adsorption of molecular chlorine onto the Ag(110) surface has been studied with low-temperature scanning tunneling microscopy, low-energy electron diffraction, and density functional theory calculations (DFT). At a coverage of 1/2 ML, chlorine forms a p(2 × 1) structure, which, with a further increase in coverage, transforms into a p(3 × 1) structure consisting of dimer rows. DFT ...
Added: June 27, 2023
Konarev D., Salavat S. Khasano, Mikhailenko M. et al., European Journal of Inorganic Chemistry 2021 Vol. 2021 No. 1 P. 86-92
New methods to prepare anionic HATNA coordination complexes from iron metal or iron carbonyls yielded (CV+)2{HATNA(FeIICl2)3}2− ⋅ 3.5C6H4Cl2, where CV+ is the crystal violet cation. The FeII atoms have a high S=2 spin state and form equilateral triangles. The exchange interaction constant between high-spin FeII is J=−4.6 cm−1 indicating antiferromagnetic coupling of spins as well as a rather ...
Added: October 22, 2022
Panina I., Balandin S., Tsarev A. et al., International Journal of Molecular Sciences 2023 Vol. 24 No. 2 P. 1
To date, a number of lantibiotics have been shown to use lipid II — a highly conserved peptidoglycan precursor in the cytoplasmic membrane of bacteria — as their molecular target. The α-component (Lchα) of the two-component lantibiotic lichenicidin (Lchα), previously isolated from the Bacillus licheniformis VK21 strain, seems to contain two putative lipid II binding ...
Added: February 21, 2023
Andronov M., Kuzmin A. V., Shestakov A. et al., Inorganica Chimica Acta 2022 Vol. 533 Article 120789
Series of anionic salts of fullerenes C60 and C70 with different metal tetraphenylporphyrins, MIITPP, where M = Co, Mn and Zn, and N, N, N, N‘, N‘-pentamethyldiaminoethane cations (PMDAE+) has been obtained in a crystalline form. Composition of the complexes is (PMDAE+)⋅(MIITPP)(C60−)⋅XC6H4Cl2 (M = Co, X = 1.25 (1), M = Mn, X = 0.75 (2) and M = Zn, X = 0.75 (3)) and {(PMDAE+)⋅ZnIITPP}2⋅(C70−)2⋅4C6H4Cl2 ...
Added: October 22, 2022
Gavryushkin P., Belonoshko Anatoly B., Sagatov N. et al., Crystal Growth & Design 2021 Vol. 21 No. 1 P. 65-74
Using molecular dynamics simulation and evolutionary metadynamic calculations, a series of structures were revealed that possessed enthalpies and Gibbs energies lower than those of aragonite but higher than those of calcite. The structures are polytypes of calcite, differing in the stacking sequence of close-packed (cp) Ca layers. The two- and six-layered polytypes have hexagonal symmetry P6322 ...
Added: January 21, 2021
Ulyana M. Zavorotnaya, Ponomarev I., Volkova Y. et al., Membranes 2023 Vol. 13 No. 5 Article 485
This paper presents research on the technology development of the hydrogen-air fuel cells with high output power characteristics using fluorine-free co-polynaphtoyleneimide (co-PNIS) membranes. It is found that the optimal operating temperature of a fuel cell based on a co-PNIS membrane with the hydrophilic/hydrophobic blocks = 70/30 composition is in the range of 60-65 °C. The ...
Added: October 5, 2023
Faraonov M., Romanenko N., Mikhailenko M. et al., New Journal of Chemistry 2021 Vol. 45 P. 13599-13607
Reduction of organic dye trans-perinone (its abbreviation is perinone) in different experimental conditions allows us to obtain and characterize radical anion {cryptand(K+)}[perinone˙−] (1) and dianion {PPN+}2[perinone2−]·2C6H4Cl2 (2) salts of this dye. The salts have layered structures. Perinone˙− radical anions form π–π stacked dimers in 1 with an effective interaction between them, whereas perinone2− dianions are ...
Added: October 21, 2022
Budkov Y., Journal of Physics: Condensed Matter 2019 Vol. 31 P. 078002-078003
We reply to the comment on our paper by Budkov (2018 J. Phys.: Condens. Matter 30 344001). ...
Added: January 4, 2019
Kalikin N., Budkov Y., Kolesnikov A. L. et al., Fluid Phase Equilibria 2021 Vol. 544-545 Article 113096
Despite the modern level of development of computational chemistry methods and technological progress, fast and accurate determination of solvation free energy remains a huge problem for physical chemists. In this paper, we describe two computational schemes that can potentially solve this problem. We consider systems of poorly soluble drug compounds in supercritical carbon dioxide. Considering that the biggest contribution ...
Added: June 1, 2021
Budkov Y., Kalikin N., Physical Review E - Statistical, Nonlinear, and Soft Matter Physics 2023 Vol. 107 No. 2 Article 024503
In this paper, we present a self-consistent field theory of macroscopic forces in spatially inhomogeneous flexible chain polyelectrolyte solutions. We derive an analytical expression for a stress tensor which consists of three terms: isotropic hydrostatic stress, electrostatic (Maxwell) stress, and stress rising from conformational entropy of polymer chains—conformational stress. We apply our theory to the ...
Added: February 15, 2023
Zavarzin Semen V., Kolesnikov A. L., Budkov Y. et al., The European Physical Journal E - Soft Matter 2022 Vol. 45 Article 24
A model is developed for describing the transport of charged colloidal particles in an evaporating sessile droplet on the electrified metal substrate in the presence of a solvent flow. The model takes into account the electric charge of colloidal particles and small ions produced by electrolytic dissociation of the active groups on the colloidal particles ...
Added: March 15, 2022
Gurina D., Budkov Y., Kiselev M. G., Journal of Molecular Liquids 2022 Vol. 352 Article 118758
A full-atomic classical molecular dynamics simulation of polylactide nanoparticle impregnation with carbamazepine in supercritical carbon dioxide was performed. The effect of temperature (333 K, 373 K), pressure (20 MPa, 40 MPa) and ethanol addition (1.7 mol.%) on the impregnation process was studied. Based on the solvent accessible surface area values it was concluded that a pressure increase and cosolvent addition ...
Added: February 19, 2022
Maslov V., Теоретическая и математическая физика 2019 Т. 201 № 1 С. 65-83
We study the process of a nucleon separating from an atomic nucleus from the mathematical standpoint
using experimental values of the binding energy for the nucleus of the given substance. A nucleon becomes
a boson at the instant of separating from a fermionic nucleus. We study the further transformations of
boson and fermion states of separation in a ...
Added: November 1, 2019
Budkov Y., Kolesnikov A. L., Polymer Science - Series C 2018 Vol. 60 No. Supplement 1 P. 148-159
Theoretical models of the conformational behavior of flexible polymer chains in mixed solvents enunciated in the world literature during the last decade are critically reviewed. Models describing different mechanisms of coil-to-globule transitions in a good solvent induced by cosolvent addition are highlighted. Special attention is given to the analysis of theoretical approaches to describing the ...
Added: November 30, 2018