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1

Speed of Ultrasound and Internal Pressure of Propanediol and Butanediol Isomers under Elevated Pressures

100%

Zorębski E., Piotrowska M., Dzida M.

Acta Physica Polonica A

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2008

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vol. 114

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issue 6A

A-265-A-270

EN

Speed of ultrasound and internal pressure of 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, and 1,3-butanediol at the temperatures ranging from 293.15 to 318.15 K and pressures up to 101 MPa are analyzed and discussed in terms of molecular structure and ability to form inter- and intramolecular hydrogen bonds.

2

Heat Capacity and Internal Pressure of Cyclopentanol at Pressures up to 100 MPa Determined by the Acoustic Method

80%

Dzida M.

Acta Physica Polonica A

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2008

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vol. 114

|

issue 6A

A-75-A-80

EN

Isobaric heat capacities and internal pressures of cyclopentanol at pressures up to 100 MPa and temperatures ranging from 293 to 318 K were determined by the acoustic method. The obtained results were compared with those of pentan-1-ol in order to study the influence of the molecular configurations comprising cyclic and normal-chain structures on pressure and temperature dependence of the thermodynamic properties. It was found that the temperature and pressure coefficients of internal pressure were sensitive to the structural organization of the liquid and reflected the character of the interactions.

3

The Interaction of Water with Glycine: A Combined Inelastic Neutron Scattering and Raman Spectra Studies

80%

Zhang P., Zhang Y., Han S., Yan Q., Li J.

Acta Physica Polonica A

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2006

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vol. 109

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issue 3

399-404

EN

The vibrational dynamics of water around glycine was investigated by using Raman spectroscopy and inelastic neutron scattering. Experiments of deuterated glycine versus deuterium were performed as comparison. The study shows that for glycine, the exchange of proton-deuteron on the active NH_3^+ side was easy, whereas there was hardly exchange on the CH_2 side. Comparing different proportion of glycine vs. water molecules we obtained that the presence of water hardly changes the main features of glycine illustrating its hydrophobic character. The intralayer hydrogen bonds of glycine crystal are difficult to be replaced due to its stronger bond than water.

4

The Response of Work Function οf Thin Metal Films to Interaction with Hydrogen

80%

Duś R., Nowicka E., Nowakowski R.

Acta Physica Polonica A

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2008

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vol. 114

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issue S

S-29-S-47

EN

The aim of this paper is to summarize the results of experiments carried out at our laboratory on the response of the work function of several thin films of transition metals and rare earth metals to interaction with molecular hydrogen. The main focus concerns the description of surface phenomena accompanying the reaction of hydride formation as a result of the adsorbate's incorporation into the bulk of the thin films. Work function changes Δ Φp caused by adsorption and reaction concern the surface, hence this experimental method is appropriate for solving the aforementioned problem. A differentiation is made between the work function changes ΔΦp due to creation of specific adsorption states characteristic of hydrides, and ΔΦp arising as a result of surface defects and protrusions induced in the course of the reaction. The topography of thin metal films and thin hydride films with defects and protrusions was illustrated by means of atomic force microscopy. For comparison, the paper discusses work function changes caused by H_2 interaction with thin films of metals which do not form hydrides (for example platinum), or when this interaction is performed under conditions excluding hydride formation for thermodynamic reasons. Almost complete diminishing of ΔΦp was observed, in spite of significant hydrogen uptake on some rare earth metals, caused by formation of the ordered H-Y-H surface phase.

5

Dielectric Relaxation in Hydrogen Bonded Urea-Based Supramolecular Polymer N,N'-di(2,2-dipentylheptyl)urea

80%

Jadżyn J., Bouteiller L., Déjardin J., Czechowski G.

|

EN

Results of the dielectric relaxation studies, performed for supramolecular polymer formed by N,N'-di(2,2-dipentylheptyl)urea dissolved in carbon tetrachloride, are presented. The measurements were done for N,N'-di(2,2-dipentylheptyl)urea concentration up to about 7% (in mole fraction) in the frequency region from 100 kHz to 100 MHz and at the temperatures from 5ºC to 50ºC. The analysis of the experimental data were performed with the Havriliak-Negami equation. In the studied range of N,N'-di(2,2-dipentylheptyl)urea concentration and temperature, the obtained values of exponentsα andβ of the Havriliak-Negami equation are equal to 0.9±0.1 and 0.7±0.1, respectively, showing an anomaly in the dielectric relaxation behavior close to the Davidson-Cole type. Two examples of the modeling of dielectric properties of the supramolecular polymer solutions were presented.

6

Formation of Hydrogen Bonds; Hydroxyl and Methyl Groups Dynamics in 2,2-dimethylbutan-1-ol and 2,3-dimethylbutan-2-ol: DFT, IINS and IR Investigations

80%

Juszyńska E., Hołderna-Natkaniec K., Massalska-Arodź M., Natkaniec I., Ściesińska E., Ściesiński J.

Acta Physica Polonica A

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2012

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vol. 122

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issue 4

765-775

EN

Dynamics of 2,2-dimethylbutan-1-ol and 2,3-dimethylbutan-2-ol have been studied by experimental spectroscopy methods, i.e., inelastic incoherent neutron scattering and infrared absorption. Experimental results were discussed and compared with the results of the quantum chemical calculations performed by semi-empirical PM3 and the density functional theory methods assuming the isolated molecule and dimer, trimer and tetramer clusters. The density functional theory modelling of vibrational spectra of monomers and OH bonded molecular clusters allows to assign the inter- and intermolecular vibrational modes observed in density of states and absorption spectra.

7

Proton Transfer in Strong Hydrogen Bonds Revealed by Infrared Spectra - Correlations between Structure and Spectra for the BrH : NH_3 Complex

70%

Szczepaniak K., Person W.

Acta Physica Polonica A

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2007

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vol. 112

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issue S

S-19-S-38

EN

Our scope is to achieve an understanding of the relation between the infrared spectrum and structure of a strong hydrogen-bonded complex, BrH : NH$_3$, and how and why this relationship is affected by the environment surrounding the complex. A series of DFT/B3LYP/6-31G(d,p) calculations was carried out for this system to obtain its structure and spectrum in different dielectric fields characterized by their relative permittivities. Changes in structure and spectrum (both frequencies and intensities) as the relative permittivity changes are explored. Calculations of spectra are made first under the harmonic approximation. In the next step the effect of anharmonicity was estimated for several different dielectric fields. The calculated anharmonic spectrum (for ε_r = 1.6) is compared with the experimentally observed infrared spectrum of the complex isolated in an Ar matrix at 10 K, obtained in our laboratory. The calculated frequencies and relative intensities for all normal modes agree with the corresponding experimental data surprisingly well. The potential usefulness of structure-spectra correlations is explored.

8

Excess thermodynamic quantities of D2O water calculated from its Raman O−D stretching spectra

61%

Georgiev M., Goutev N., Nickolov Z., Georgiev G.

Open Physics

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2005

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vol. 3

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issue 1

104-114

EN

Excess thermodynamic functions of D2O water have been calculated from the vibrationally decoupled O−D stretching spectra of very dilute solutions of HOD in H2O. Comparison of the results with reference calorimetric data for water showed a good correspondence for excess heat capacity above the melting point of ice. The excess enthalpy at the melting point also coincides well with latent heat of melting.

Refine search results

Speed of Ultrasound and Internal Pressure of Propanediol and Butanediol Isomers under Elevated Pressures

Heat Capacity and Internal Pressure of Cyclopentanol at Pressures up to 100 MPa Determined by the Acoustic Method

The Interaction of Water with Glycine: A Combined Inelastic Neutron Scattering and Raman Spectra Studies

The Response of Work Function οf Thin Metal Films to Interaction with Hydrogen

Dielectric Relaxation in Hydrogen Bonded Urea-Based Supramolecular Polymer N,N'-di(2,2-dipentylheptyl)urea

Formation of Hydrogen Bonds; Hydroxyl and Methyl Groups Dynamics in 2,2-dimethylbutan-1-ol and 2,3-dimethylbutan-2-ol: DFT, IINS and IR Investigations

Proton Transfer in Strong Hydrogen Bonds Revealed by Infrared Spectra - Correlations between Structure and Spectra for the BrH : NH_3 Complex

Excess thermodynamic quantities of D2O water calculated from its Raman O−D stretching spectra