молекулярное моделирование

VIBRONIC SPECTRA AND STRUCTURE OF EXITED STATES OF POLYATOMIC MOLECULES

The methods of determination of molecular model parameters in exited electronic states are considered. Structural-dynamic models polyatomic molecules are developed using a semi-empirical method of hybridized atomic orbitals. It is shown that the electronic-vibrational spectra make it possible to identify the tautomeric forms in different phases states, taking into account the intermolecular interaction.

 

The Vibrationai Spectra of 2-Biphenylmethanol and their Interpretation by Using of Molecul Structural-Dynamical Model Taking into Account Mechanical Anharmonicity

Using hybrid density functional (B3LYP/6-31 (d)) the calculation of the geometry, electro-optical parameters, quartic force field and vibrational spectra of the 2-biphenylmethanol molecule were performed. The vibrational analysis was implemented and the full interpretation of its IR (400-3800 cm^(-1)) and Raman (50-3600 cm^(-1)) spectra was given.

IR Spectrum of the Methyl-β-D-Glucopyranoside and its Interpretation on Basis Structural-Dynamic Model Construction

Structural-dynamic models of the methyl-β-D-glucopyranoside molecule are constructed by density functional method in bases 6-31 G(d), 6-31+G (d, p). 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 400-3700 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.

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).

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.

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.

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.

Influence of the H-bonding to the Structure and Vibrational Spectrum of 2,3-di-O-nytro-methyl-β-D-glucopyranoside

Structural-dynamic models of 2,3-di-O-nytro-methyl-β-D-glucopyranoside and its H-complexes were constructed by density functional method using the functional B3LYP in the 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 spectrum of the 2,3-di-O-nytromethyl-β-D-glucopyranoside and ethanol complexes is presented in range 600–3700 cm–1.

Pages