- Tytuł:
-
Transformacje strukturalne w kryształach wywołane reakcjami fotochemicznymi
Structural transformations in crystals induced by photochemical reactions - Autorzy:
-
Turowska-Tyrk, I.
Bąkowicz, J. - Powiązania:
- https://bibliotekanauki.pl/articles/171650.pdf
- Data publikacji:
- 2014
- Wydawca:
- Polskie Towarzystwo Chemiczne
- Tematy:
-
reakcje fotochemiczne w kryształach
struktura kryształu
struktura cząsteczki
zmiany strukturalne
rentgenowska analiza strukturalna
krystalografia
photochemical reactions in crystals
crystal structures
molecular structure
structural changes
X-ray structure analysis
crystallography - Opis:
- Structural changes induced in crystals by photochemical reactions were presented. The changes concern: a) the distances between neighbouring reactant molecules and their mutual orientation in the case of intermolecular reactions, b) the distances and angles between fragments of a molecule for intramolecular reactions, c) the position of molecules in crystals, d) geometry of hydrogen bonds, e) cell constants, and f) the content of product molecules in crystals. For most intramolecular reactions, the distances between reactive atoms are constant for a long time in phototransformation and decrease rapidly at its end (Figs. 3 and 5). In the case of intermolecular reactions, the distances between reactive atoms of reactant molecules decrease linearly along with the phototransformation of crystals (Fig. 7). Additionally, unreacted molecules become, to a certain degree, similar to product molecules in terms of their shape (Figs, 4 and 8). Reactant and product molecules do not assume a fixed place in crystals. Product molecules change their orientation towards that of which is observed in a pure product crystal and reactant molecules gradually move away from the position they took in pure reactant crystals. All this has an influence on the geometry of hydrogen bonds existing in crystals (Fig. 9). The above-mentioned structural transformations find their expression in values of cell constants (Fig. 10). The factors influencing the photoreactivity of molecules in crystals were also described. Knowledge of crystal and molecular structures of partly reacted crystals, determined thanks to X-ray structure analysis which is a branch of crystallography, reveals the behaviour of molecules in crystals in which photochemical reactions proceed and helps to understand a pathway of these reactions.
- Źródło:
-
Wiadomości Chemiczne; 2014, 68, 5-6; 381-402
0043-5104
2300-0295 - Pojawia się w:
- Wiadomości Chemiczne
- Dostawca treści:
- Biblioteka Nauki