1. |
- Koptyug, Andrey, 1956-, et al.
(author)
-
Spin-locking in concentration-narrowed OD ESR spectra
- 1989
-
In: Chemical Physics. - Amsterdam : Elsevier. - 0301-0104 .- 1873-4421. ; 138:1, s. 173-178
-
Journal article (peer-reviewed)abstract
- The effect of spin- locking under the action of a resonance rf field of large amplitude has been observed in the optically detected ESR spectra (OD ESR) of radical-ion pairs both in strong and weak magnetic fields. "Hampering" of singlet-tgriplet transitions occurs for concentrations of aromatic acceptors in non polar solutions at room temperature from 10e-4 to 1 M. It is proposed that in spite of strong concentration narrowing OD ESR signals are inhomogeneously broadened. This can be due to neutral molecule- radical-anion aggregate formation.
|
|
2. |
|
|
3. |
- Maliniak, Arnold, et al.
(author)
-
NUCLEAR-SPIN RELAXATION STUDY OF HYDROGEN-BONDING IN SOLUTIONS OF QUINUCLIDINE
- 1984
-
In: Journal of Physical Chemistry. - 0022-3654. ; 88:23, s. 5628-5631
-
Journal article (peer-reviewed)abstract
- The intermolecular hydrogen bonds formed by quinuclidine together with different solvents (benzene, chloroform, methanol, trifluoroacetic acid) are studied by using NMR relaxation measurements. The carbon-1 3 and nitrogen-I4 relaxation rates are determined and Woessner's model for dipole relaxation in a symmetric rotor is applied. The different values for the ratio between the rotational diffusion constants RII and R, in different solvents and at different temperatures are discussed in terms of molecular reorientation anisotropy due to hydrogen bonds formed by quinuclidine and the solvent. From the nitrogen-14 relaxation rates the quadrupole coupling constants (QCC) are evaluated and compared with the results of quantum-chemical calculations of electric field gradients performed on model systems.
|
|
4. |
- Panas, Itai, 1959, et al.
(author)
-
A THEORETICAL-STUDY OF THE PEROXO AND SUPEROXO FORMS OF MOLECULAR-OXYGEN ON METAL-SURFACES
- 1989
-
In: Chemical Physics Letters. - 0009-2614. ; 153:5, s. 458-464
-
Journal article (peer-reviewed)abstract
- Simple cluster model calculations have been performed for the peroxo and superoxo forms of O2 on metal surfaces. The ionization spectra of superoxo-O2 on Ag(110) and Pt(111) and for peroxo-O2 on Ag(110) are predicted in good agreement with the most reliable experimental measurements. It is shown that the large qualitative difference between these spectra can be used to decide experimentally whether O2 is chemisorbed in the peroxo or superoxo form. The O---O bond distance is calculated to be 1.32 Å for superoxo-O2 and 1.43 Å for peroxo-O2 in good agreement with the most recent NEXAFS measurements on Pt(111) and Ag(110), respectively. A problem in a recent analysis of a UPS spectrum for obtaining the O---O bond distance is pointed out.
|
|
5. |
|
|
6. |
|
|
7. |
|
|
8. |
|
|
9. |
|
|
10. |
- Blaszczak, Z., et al.
(author)
-
Electrooptical Kerr Effect Studies of Hemoglobin
- 1985
-
In: Physical Optics of Dynamic Phenomena & Processes in Macromolecular Systems: Proceedings of the 27th Microsymposium on Macromolecules, Prague; ed. by Blahoslav Sedlacek. - 311010234X ; , s. 325-328
-
Book chapter (other academic/artistic)
|
|