Wszystkie pola: 61.66.Fn - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Optical Properties of Europium Compounds with L- and DL-α-Alanine-Hydroxamic Acids
Autorzy:: Legendziewicz, J.
Gawryszewska, P.
Gałdecka, E.
Gałdecki, Z.
Powiązania:: https://bibliotekanauki.pl/articles/1945683.pdf
Data publikacji:: 1996-08
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 78.20.Wc
78.55.Hx
61.66.Fn
78.20.Dj
Opis:: Two of europium complexes with L- and DL-α-alanine-hydroxamic acids were synthesized. To our knowledge they are the first examples of X-ray and spectral data of lanthanide single crystals with hydroxamic acid derivatives. Both compounds consist of dimers in their structures, formed by two OH bridging groups of amino-hydroxamic acid molecules. Besides, two metal ions are chelated by CO and OH groups, forming five-membered rings. In the complex with L-ligand, different than in the DL-one, two additional perchloric acid molecules are included in crystal cavities and form hydrogen bondings with nitrogen and oxygen atoms of the ligand. Absorption, emission and excitation spectra were measured and analyzed at room and low temperatures. Structural effect of ligand chirality was found and its spectroscopic consequences are reported. The effect of the dimeric structure on spectroscopic properties is discussed.
Źródło:: Acta Physica Polonica A; 1996, 90, 2; 439-446
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 2.

Tytuł:: Structure and Spectroscopy of Selected Lanthanide Compounds with Coordination Number from 9 to 6
Autorzy:: Legendziewicz, J.
Powiązania:: https://bibliotekanauki.pl/articles/1945488.pdf
Data publikacji:: 1996-07
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 61.66.Fn
78.20.Dj
78.20.Wc
78.55.Hx
78.66.-w
Opis:: The lecture deals with a group of lanthanide compounds in which some structural factors influence, in a special way, spectroscopic properties of the systems under investigation. The following systems were chosen: three with polymeric structure, two of the dimer type, one a pseudo-dimer system with coordination number (C.N.) = 7, and an octahedral compound of LnL$\text{}_{6}$ type. The crystal structures of the systems under consideration will be shown, their absorption and excitation spectra will be presented and confronted with X-ray data. Radiative and nonradiative processes will be considered and the role of cooperative interactions analyzed. Some aspects of dynamics in solids will be done, too.
Źródło:: Acta Physica Polonica A; 1996, 90, 1; 127-142
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 3.

Tytuł:: Optical Properties and Structure of Ln(NCS)(Hmpa)$\text{}_{4}$-(SCN)$\text{}_{2}$- HgCl(SCN)
Autorzy:: Gałdecka, E.
Gałdecki, Z.
Amirkhanov, V.
Kern, K.
Legendziewicz, J.
Powiązania:: https://bibliotekanauki.pl/articles/1945687.pdf
Data publikacji:: 1996-08
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 78.20.Wc
78.55.Hx
78.20.Dj
78.66.-w
61.66.Fn
Opis:: Praseodymium, neodymium and europium complexes of the formula Ln(NCS)(Hmpa)$\text{}_{4}$-(SCN)$\text{}_{2}$-HgCl(SCN) were synthesised from non-aqueous solutions. The structure of neodymium complexes was determined by X-ray diffraction. The crystals of the title compounds crystallise in the space group Cc, where lanthanide ions are coordinated to seven ligand groups: four of Hmpa molecules and three SCN¯ ions. The compounds were characterised by IR, luminescence, excitation and absorption spectra at 6, 77, and 298 K. Probabilities of electronic transitions for Pr$\text{}^{3+}$ ion were examined at 6 K and at room temperatures. Vibronic components were observed and analysed on the basis of IR and Raman data. Asymmetric arrangement of Ln ions was found from X-ray analysis and its influence on optical properties of active centre was discussed.
Źródło:: Acta Physica Polonica A; 1996, 90, 2; 469-476
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

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