Izvestiya of Saratov University.
ISSN 1817-3020 (Print)
ISSN 2542-193X (Online)


molecular modeling

Polymorphism manifestations and aqueous environment influence on the physico-chemical properties of modified succinic acid

Background and Objectives: Succinic acid is widely used in medicine, in particular, in the treatment of cardiological, neurological and endocrinological diseases. An urgent task of pharmacology is to increase the degree of bioavailability and solubility of drugs. One of ways to increase the therapeutic effect of drugs is the development of their polymorphic modifications, which contribute to a more pronounced therapeutic effect.

Mechanisms of intermolecular interaction of mitoxantrone with targeted delivery polyelectrolyte capsules

Background and Objectives: Polyelectrolyte capsules are one of the most promising materials for targeted drug delivery – one of the rapidly developing areas of modern chemistry, pharmacology and medicine. They have a wide range of applications due to various methods of controlling their physical and chemical properties.

Investigation of the influence of the hydrogen bonding on the structure and vibrational spectra of biphenylmethanols

Using density functional method (B3LYP/6-31G*), the structures of the biphenylmethanols, their h-bond complexes and methanol h-bond complexes, energies, dipole moments, polarizabilities, frequencies of normal vibrations (in harmonic approximation) and their intensities in vibrational spectra were simulated.

IR Spectra of Cyclohexanol, Structural-Dynamic Models of Molecule

In wide temperature range IR spectra of cyclohexanol in different phase state (plastic phase, crystal phases II, III) have been measured in range 600–3600 см–1. Using density functional method B3LYP/6-31G structural – dynamic models of conformers of cyclohexanol molecule, which differs from each other by orientation of hydroxyl group relatively carbonic ring and cyclohexan, have been constructed. The energy, structure, dipole moments, polarizabilities and the frequencies of the normal modes in harmonic approximation and IR intensities have been calculated.

IR Spectra of Triphenyl Phosphite and Their Interpretation by Molecular Modeling

Background and Objectives: IR spectra of triphenyl phosphite (TPhPh) were measured in liquid (at 320 K), glassy and glacial phases and in hexagonal (metastable) and monoclinic (stable) crystal phases at 12 K. The observed differences in the spectra is a consequence of the implementation of the conformers of different types in the sample. To substantiate this hypothesis, structurally dynamic models of the three most probable conformers (I –III) were built. The conformers are different in angles of rotation of the phenyl rings around the C-O bonds.

Influence of the Hydrogen Bond on the IR-spectrum and Structure of Molecular Complex of Diamond Nanoparticles and DNA Bases

Background and Objectives: Using molecular modeling by the density functional theory method we analyze a hydrogen bonds formation and their influence on IR-spectrum and structure of molecular complex which is formed as the interaction of complementary couple of DNA nucleobases adenine and timin and nanodiamonds surrounded with carboxylic groups. As an example of nanodiamonds adamantine has been used. Intermolecular forces and structure of hydrogen bonds are investigated.

Molecular Modeling and Vibrational Spectra of 4,4,’-clorobenzophenone

Vibrational infrared and Raman spectra of 4,4’-chlorobenzophenone have been measured at room temperature in the ranges 400–3200 and 0–3200 cm−1 respectively. Modeling of structure and vibrational spectra has been performed by a density functional theory method B3LYP/6-31+g(d) and 6-31-g(d). Energy, structure, components of the dipole moment and polarizability tensor, force constants, frequencies of normal modes in harmonic approximation and their intensities in the IR and Raman activity have been calculated. Interpretation of measured spectra is given.

Calculation of Structure and IR Spectrum of the 2,3-di-O-nytro-methyl-β-D-Glucopyranoside Molecule by Density Functional Method

Structural-dynamic models of the 2,3-di-O-nytro-methyl-β-Dglucopyranoside molecule are constructed by density functional method in basis 6-31G(d). Energies, structures, dipole moments, polarizabilities, frequencies of normal modes in harmonic approximation and IR intensities have been calculated. Interpretation of IR absorption spectrum is presented in range 600–3700 cm–1. Advantages of model, which was constructed, compared with model, which bases on using valence-force field method and valency-optical theory, are discussed.

Intermolecular Interaction in Two-component Compounds of Nanodiamonds and Doxorubicin

Background and Objectives: Detonation nanodiamond (ND) is one of the most promising materials for targeted drug delivery – one of rapidly developing areas of modern chemistry, pharmacology and medicine. Wide possibilities of surface modification and advantageous dimensions make nanodiamonds very attractive objects for using in the drug delivery process. A number of studies have shown that therapeutic efficacy of drugs is enhanced and their toxicities may be attenuated with immobilization on the enriched ND. There are a lot of drug immobilization methods on ND surfacy.

The Influence of Hydrogen Bond on the Structure and IR Spectrum of Triphenyl Phosphite

Background and Objectives: The IR spectra of triphenyl phosphite (TPP) have been measured at temperatures of 12 and 320 K in five phase states: crystalline (monoclinic and hexagonal phases), “glacial”, amorphous and liquid. It is necessary to clarify the effect of hydrogen bonding on the structure and IR spectrum of TPP. Materials and Methods: The IR spectra were measured on the IFS-88 spectrophotometer using the OPUS software. The spectral resolution was 2 cm^(-1).

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