2007
Interactions of organic molecules at grain boundaries in ice: A solvatochromic analysis
HEGER, Dominik a Petr KLÁNZákladní údaje
Originální název
Interactions of organic molecules at grain boundaries in ice: A solvatochromic analysis
Název česky
Interakce organických molekul na hranicích zrn ledu: Solvatochromní analýza
Autoři
HEGER, Dominik (203 Česká republika) a Petr KLÁN (203 Česká republika, garant)
Vydání
Journal of Photochemistry and Photobiology A: Chemistry, Amsterdam, The Netherlands, Elsevier Science, 2007, 1010-6030
Další údaje
Jazyk
angličtina
Typ výsledku
Článek v odborném periodiku
Obor
10401 Organic chemistry
Stát vydavatele
Nizozemské království
Utajení
není předmětem státního či obchodního tajemství
Impakt faktor
Impact factor: 1.911
Kód RIV
RIV/00216224:14310/07:00020320
Organizační jednotka
Přírodovědecká fakulta
UT WoS
000245882900019
Klíčová slova anglicky
Photochemistry; Ice; Solvatochromic
Štítky
Příznaky
Mezinárodní význam, Recenzováno
Změněno: 23. 6. 2009 15:12, prof. RNDr. Petr Klán, Ph.D.
V originále
Empirical solvent polarity parameters were used to evaluate the nature and magnitude of the intermolecular interactions of eight dipolar organic solvatochromic indicators in aqueous solutions frozen at 253 or 77 K, using the concept that is generally employed to study the polarity of liquid solvents or solid surfaces. ET(30), ET(33), and as well as alpha, acceptor number (AN) (hydrogen-bond donation ability), beta (hydrogen-bond acceptor ability), and pi* (polarity/polarizability) parameters were obtained by measuring the differences in the shifts of the absorption spectra of the probes. It was found that hydrogen-bond and electron pair donating interactions were significant contributors to the polarity of a probe environment in ice and, at the same time, they were found to be substantially larger than those measured in liquid aqueous solutions and relatively insensitive to the sample temperature. While the former interaction type is attributed rather to the presence of water in a close vicinity of the probe molecules, the latter is evidently connected with the interprobe interactions within the self-assembled molecular aggregations in conjunction with the water probe interactions. The solvatochromic analysis revealed very weak dipole dipole interactions (pi*) but the results are inconclusive. The data are consistent with a model according to which, upon freezing the aqueous solutions, the organic solute molecules are ejected to the grain boundaries to form highly concentrated liquid or frozen mixtures of organic and water molecules, having a high degree of complexity and exhibiting specific intermolecular interactions. Evaluation of the intermolecular polar interactions at the grain boundaries in ice should be of a great value in advancing our understanding of physical and chemical processes occurring in natural ice and snow.
Česky
Empirical solvent polarity parameters were used to evaluate the nature and magnitude of the intermolecular interactions of eight dipolar organic solvatochromic indicators in aqueous solutions frozen at 253 or 77 K, using the concept that is generally employed to study the polarity of liquid solvents or solid surfaces. ET(30), ET(33), and as well as alpha, acceptor number (AN) (hydrogen-bond donation ability), beta (hydrogen-bond acceptor ability), and pi* (polarity/polarizability) parameters were obtained by measuring the differences in the shifts of the absorption spectra of the probes. It was found that hydrogen-bond and electron pair donating interactions were significant contributors to the polarity of a probe environment in ice and, at the same time, they were found to be substantially larger than those measured in liquid aqueous solutions and relatively insensitive to the sample temperature. While the former interaction type is attributed rather to the presence of water in a close vicinity of the probe molecules, the latter is evidently connected with the interprobe interactions within the self-assembled molecular aggregations in conjunction with the water probe interactions. The solvatochromic analysis revealed very weak dipole dipole interactions (pi*) but the results are inconclusive. The data are consistent with a model according to which, upon freezing the aqueous solutions, the organic solute molecules are ejected to the grain boundaries to form highly concentrated liquid or frozen mixtures of organic and water molecules, having a high degree of complexity and exhibiting specific intermolecular interactions. Evaluation of the intermolecular polar interactions at the grain boundaries in ice should be of a great value in advancing our understanding of physical and chemical processes occurring in natural ice and snow.
Návaznosti
| GA205/05/0819, projekt VaV |
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| MSM0021622412, záměr |
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