The local ordering and features of the molecular mobility of water confined in voids of a pure silica mordenite were studied using the molecular dynamics simulation over a temperature range from 298 to 163 K. The simulated system was a fragment of mordenite consisted of 2 × 2 × 4 unit cells filled with 384 water molecules. Three different water models: SPCE, SPCF, and TIP5P were considered. To study the effect of nanoconfinment, the results were compared with bulk water. The modeling suggests that at room temperature, a 2D (in c and b directions of the mordenite cell) water diffusion takes place, while upon cooling, the diffusion in b direction essentially slows down. The analysis of microstructure shows that the pores prevent the formation of a full tetrahedral structure of water environment that results in formation of several water substructures. A detailed analysis of water reorientational motion was carried out and the activation energies were determined from temperature dependences of the correlation times. Of the three water models considered, SPCE demonstrated the best performance. The results obtained can be helpful for interpretation of experimental temperature dependences of NMR relaxation rates for water molecules confined in porous media with complex topology.
Translated title of the contributionСтруктура и динамика воды в микропористом мордените
Original languageEnglish
Pages (from-to)805-818
Number of pages14
JournalApplied Magnetic Resonance
Volume55
Issue number8
DOIs
StatePublished - 1 Aug 2024
Event21th International School-Conference «Magnetic resonance and its applications» - Saint Petersburg, Russian Federation
Duration: 1 Apr 20245 Apr 2024
Conference number: 21
http://spinus.spb.ru

    Scopus subject areas

  • Condensed Matter Physics
  • Physical and Theoretical Chemistry
  • Materials Science (miscellaneous)

    Research areas

  • Activation energy, Confined water, Correlation times, Molecular dynamics, Zeolites

ID: 124944986