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Optimized geometry, vibration (IR and Raman) spectra and nonlinear optical activity of p-nitroanilinium perchlorate molecule: A theoretical study

Tamer O., Atalay A. S., Avci D., Atalay Y., Tarcan E., Marchewka M. K.

Materials Science Poland

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2016

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Vol. 34, No. 1

192--203

EN

The molecular modeling of p-nitroanilinium perchlorate molecule was carried out by using B3LYP and HSEH1PBE levels of density functional theory (DFT). The IR and Raman spectra were simulated and the assignments of vibrational modes were performed on the basis of relative contribution of various internal co-ordinates. NBO analysis was performed to demonstrate charge transfer, conjugative interactions and the formation of intramolecular hydrogen bonding interactions within PNAPC. Obtained large dipole moment values showed that PNAPC is a highly polarizable complex, and the charge transfer occurs within PNAPC. Hydrogen bonding and charge transfer interactions were also displayed by small HOMO-LUMO gap and molecular electrostatic potential (MEP) surface. The strong evidences that the material can be used as an efficient nonlinear optical (NLO) material of PNAPC were demonstrated by considerable polarizability and hyperpolarizability values obtained at DFT levels.

2

Vibrational and thermal behaviour of melaminium butyrate crystals

Marchewka M. K., Ratajczak H.

Bulletin of the Polish Academy of Sciences. Chemistry

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2002

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Vol. 50, No. 3

335-345

EN

The crystals of a new melaminium salt, i.e. melaminium butyrate were obtained by slow evaporation of an aqueous solution at room temperature. The room temperature powder infrared and R'aman measurements were carried out. DSC measurements clearly point to the occurrence of the phase transition of the first order at ca, 239 K. No detectable signal was observed during powder test for second harmonic generation.

3

Anharmonic effects on the OH stretching vibrations of the Na5H3(SeO4)4x2H2O crystal

Ratajczak H., Barnes A. J., Baran J., Marchewka M. K., Yaremko A. M.

Bulletin of the Polish Academy of Sciences. Chemistry

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2001

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Vol. 49, No. 1

1-8

EN

Polarized infrared spectra of pentasodium trihydrogen tetraselenate dihy-drate, Na(5)H(3)(SeO4)(4)2H(2)O, are analysed using a model which takes account of the Fermi resonance interactions between the OH stretching vibrations and various combination tones. It is demonstrated that the short, centrosymmetric, hydrogen bond of the hydro-gendisefenate anion generates an intense broad absorption whose spectral features can be described taking into consideration strong interaction between the va (OHO) stretching vibration and lattice phonons, while the longer hydrogen bond linking hydrogenselenate ions to the hydrogendiselenate anion gives a typical ABC band structure.

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Vibratial and DSC investigations of the (NH4)4H2(SeO4)3 crystal

Baran J., Marchewka M.K., Drozd M., Czapla Z.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 2

355-367

EN

Polarized Raman and powder IR spectra for a (NH4)4H3(SeO4)3 crystal were measured at room temperature and discussed with relation to the crystal structure. Additionally, the reflection polarized IR spectra were measured. The transition into a metastable phase was observed for the first heating DSC scan. In following cooling and heating scans 5 and 7 phase transitions, respectively, were observed. No changes were noticed between the IR spectra of the fresh sample and that which was heated up to a superionic phase and cooled down. A strong reaction between the KBr windows and the sample occurs when heating to the superionic phase.