A model study of dickite intercalated with formamide and N-methylformamide

Autor(en)

Eva Scholtzova, Lubomir Benco, Daniel Tunega

Abstrakt

Local geometry and orientation of intercalated molecules of formamide (FA) and N-methylformamide (NMFA) in the clay mineral dickite (D) was studied by means of Density Functional Theory (DFT) calculations. Ten configurations with different orientation of the intercalated molecule were investigated for both D_FA and D_NMFA intercalates. Four groups of relaxed structures sorted by the calculated total electronic energy were found in both cases. The experimental geometry of the D_FA intercalate was denoted as the most stable structure from the investigated models. The differences in the total electronic energy of all D_FA configurations are within the interval of ∼92 kJ/mol. On one hand FA forms intercalates specifically and a close relation between the orientation of the FA molecules in the interlayer space and the stability of a particular configuration has been observed. On the other hand, N-methylformamide forms intercalated structures non-specifically. Small differences in the total energy, not larger than 18 kJ/mol, are observed for different orientations of the NMFA molecules The reorientation of the intercalated molecules has only a small effect on the stabilization of the D_NMFA intercalate what is in contrast with the D_FA intercalate. It was also observed that the experimental D_NMFA configuration is not the most stable. A small variation of the total electronic energy of different configurations correlates with small changes of the orientation of the dipole moment of the intercalated NMFA molecule.

Organisation(en)

Computergestützte Materialphysik, Institut für Theoretische Chemie

Externe Organisation(en)

Slovenian Academy of Sciences and Arts

Journal

Physics and Chemistry of Minerals

Band

35

Seiten

299-309

Anzahl der Seiten

11

ISSN

0342-1791

DOI

https://doi.org/10.1007/s00269-008-0223-9

Publikationsdatum

2008

Peer-reviewed

Ja

ÖFOS 2012

103015 Kondensierte Materie, 104022 Theoretische Chemie

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/6988a3c6-b618-4289-9395-6913e8af74e3