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1

Analysis of Electron Density in trans-N,N'-Bis-(R-salicylidene)-1,2-cyclohexanediamines

Dziembowska T., Majerz I.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 5-6

911-920

EN

The hydrogen bonds in three tautomeric forms of trans-N,N-bis-(R-salicylidene)- 1,2-cyclohexanediamine (R = H, 5-NO2, 4,6-di-OCH3 and 3,5-di-Cl) have been studied by DFT calculations and topology of density charge function according to Bader’s AIM theory. Comparison of the CP values at the H…N and H…O bond critical points (BCP) for the compounds studied has revealed the effect of substituents on the hydrogen bonds strengths in the two chelate rings of trans-N,N-bis-(R-salicylidene)-1,2-cyclohexanediamines.

2

Dimerization of 1,8-Diaminonaphthalene. DFT Theoretical, Ifra-red, raman and Inelastic Neutron Scattering Studies

Majerz I., Pawlukojć A., Sobczyk L., Grech E., Nowicka-Scheibe J.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 2-3

409-417

EN

Infra-red (IR), Raman (R) and inelastic neutron scattering (INS) studies were performed on solid 1,8-diaminonaphthalene. Calculations by using HF and DFT methods showed that very good reproduction of the dimeric structure found in the solid state yields the DFT method on the B3LYP/6-31G** level. The characteristic motif of dimers is an eight-membered ring with two intramolecular (highly bent) and two intermolecular N-H___Nhydrogen bridges. The four outer N-H groups remain non-bonded. This leads to a complicated pattern of vibrational spectra. No agreement between calculated and experimental (IR, R) spectra in the range of (NH2) vibrations was found.Arelatively good coincidence of experimental and theoretically predicted spectra is observed in the middle and low frequency regions, especially when analysing the INS spectra for dimeric species. The dimerization leads to a marked change in modes connected with torsional vibrations of NH2 groups.

3

Transformation of the 3-oxoazabicyclo[2.2.2]octane pentachlorophenol complex into the 3-hydroxy-3-methoxyazabicyclo[2.2.2]octane pentachlorophenolate

Majerz I., Malarski Z., Lis T.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 2

325-334

EN

The transformation of the 3-oxoazabicyclo[2.2.2]octane pentachlorophenol complex in methanol (and CH3OD) solution into the 3-hydroxy-3-methoxy-azabicyclo[2.2.2]octane pentachlorophenolate is described. The presence of the acidic phenol proton were sufficient to promote such a reaction. The crystal structure of the 3-hydroxy-3-methoxyazabicyclo[2.2.2]octane pentachlorophenolate and its deuterated analoque were determined by X-ray method. IR spectra indicate an ionic character of the complexes and a moderately strong N(+)-H...O(-) and N(+)-D...O(-) hydrogen bonds with the isitopic ratio v(NH)/v(ND) equal to 1.22. Weaker intermolecular O-H...O(-) and O-D...O(-) hydrogen bridges exhibit the isotopic ratio v(OH)/v(OD) 1.34.

4

Infrared studies on the structural phase transitions in (n-C3H7NH3)2 SbBr5 and (n-C3H7NH3)3Sb2Cl9

Bator G., Jakubas R., Majerz I.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 2

314-324

EN

Internal vibration modes of(n-C3H7NH3)2SbBr5 and (n-C3H7NH3)3Sb2Cl9 were studied through their phase transitions using the infrared spectroscopy. The studies show that the vibrational states of the n-propylammonium cations change considerably during the phase transitions. The v(CC), v(CN) and v-s(NH) bands are very sensitive to the phase transition at 154 K in (n-C3H7NH3)2SbBr5, and at 232 K in (n-C3H7NH3)3Sb2Cl9. IR spectra point out the key role of the n-propylammonium cations in the phase transition mechanism of both crystals.