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1

Fragmentation and Kinetic Energy Release of Ions Produced from C_2H_5OH

100%

Szot E., Głuch K., Wójcik L.

Acta Physica Polonica A

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2013

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vol. 123

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issue 5

797-799

EN

The high resolution double focusing mass spectrometer of reversed Nier-Johnson geometry was used in research of ionization and fragmentation processes of ethanol molecules C_2H_5OH. Using the mass-analyzed ion kinetic energy technique, fragmentation paths and kinetic energy release distributions were examined for the four fragmentation reactions: C_2H_6O^{+} → C_2H_5O^{+}, C_2H_6O^{+} → C_2H_3O^{+}, CH_3O^{+} → CH_2O^{+} and CH_3O^{+} → CHO^{+}. For all fragment ions from these reactions mean values of kinetic energy release 〈ε〉 were determined. We calculated mean values of 〈ε〉 as 22.70 meV, 62.15 meV, 30.25 meV, and 117.20 meV for C_2H_5O^{+}, C_2H_3O^{+}, CH_2O^{+}, and for CHO^{+} ions, respectively.

2

NMR study of heterogeneity in pyridine-N-oxide...HCl crystal

75%

Balevicius V., Gacesa A., Plavec J.

Open Physics

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2004

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vol. 2

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issue 1

120-131

EN

An origin of narrow 1H NMR signals in pyridine-N-oxide (PyO)...HCl crystal has been investigated by means of MAS, SPEDAS, NOESY and COSY techniques. Spectra of crystalline samples are compared with those of solid phase obtained from liquid PyO...HCl solutions (in acetonitile/H2O) after the heterogeneous phase separation. It has been concluded that partially resolved peaks in 1H NMR spectra of solids are related with heterogeneity of spin system and presence of different H-bond clusters of water molecules. NOESY spectra show no cross-peaks even at very long mixing time (500 ms). This indicates there is no exchange process between spins causing different peaks, and thus the corresponding molecular aggregates are captured in “islands of mobility8 without any channels sufficient for exchange. Appearance of MAS side bands as “pseudo8 cross-peaks in 2D NMR spectra using MAS/COSY technique is reported. In the case of accidental coincidence of spinning frequency (ωMAS) with spectral distances between some diagonal signals, intensive non-diagonal peaks are observed at the corresponding cross-positions. A misleading conclusion concerning spin coupling is easy to avoid using various ωMAS.

3

Towards relativistic ECP / DFT description of chemical bonding in E112 compounds: spin-orbit and correlation effects in E112X versus HgX (X=H, Au)

63%

Zaitsevskii A., Rykova E., Mosyagin N., Titov A.

Open Physics

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2006

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vol. 4

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issue 4

448-460

EN

The relativistic effective core potential (RECP) approach combined with the spin-orbit DFT electron correlation treatment was applied to the study of the bonding of eka-mercury (E112) and mercury with hydrogen and gold atoms. Highly accurate small-core shape-consistent RECPs derived from Hartree-Fock-Dirac-Breit atomic calculations with Fermi nuclear model were employed. The accuracy of the DFT correlation treatment was checked by comparing the results in the scalar-relativistic (spin-orbit-free) limit with those of high level scalar-relativistic correlation calculations within the same RECP model. E112H was predicted to be slightly more stable than its lighter homologue (HgH). The E112-Au bond energy is expected to be ca. 25–30 % weaker than that of Hg-Au. The role of correlations and magnetic (spin-dependent) interactions in E112-X and Hg-X (X=H, Au) bonding is discussed. The present computational procedure can be readily applied to much larger systems and seems to be a promising tool for simulating E112 adsorption on metal surfaces.

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2 Open Physics

1 Acta Physica Polonica A

1 2013

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1 Balevicius V.

1 Gacesa A.

1 Głuch K.

1 Mosyagin N.

1 Plavec J.

1 Rykova E.

1 Szot E.

1 Titov A.

1 Wójcik L.

1 Zaitsevskii A.

Fragmentation and Kinetic Energy Release of Ions Produced from C_2H_5OH

NMR study of heterogeneity in pyridine-N-oxide...HCl crystal

Towards relativistic ECP / DFT description of chemical bonding in E112 compounds: spin-orbit and correlation effects in E112X versus HgX (X=H, Au)