Bulletin of the Korean Chemical Society

Korean Chemical Society (대한화학회)
권호 표지
DOI QR코드

DOI QR Code

Molecular Dynamics Simulation Studies of Zeolite A. Ⅶ. Structure and Dynamics of $H^+$ ions in a Nom-Rigid Dehydrated H12-A Zeolite Framework

  • Published : 1999.03.20
Download PDF
⟨ Previous Next ⟩

Abstract

In the present paper, we report a molecular dynamics (MD) simulation study for the structure and dynamics of H+ ions in non-rigid dehydrated H12-A zeolite framework at 298.15 K, using the same method we used in our previous studies of rigid and non-rigid zeolite-A frameworks. It is found that two different structures appear, depending on the choice of the Lennard-Jones parameter (σ) for the H+ ion, as is also observed in the study of rigid dehydrated H12-A zeolite framework, but the ranges of σ are different for the two structures. It is also found that some of the H+ ions exchanged their sites without changing the number of H+ ions at each site. The agreement between experimental and calculated structural parameters for non-rigid dehydrated H12-A zeolite is generally quite good. The calculated IR spectrum by Fourier transform of the total dipole moment auto-correlation function shows two major peaks, one around 2700 cm-1 and the other around 7000 cm-1. The former appears in the calculated IR spectra of non-rigid zeolite-A framework only system and the latter remains unexplained except, perhaps, as an indication of a new formation of a vibrational mode of the framework due to the adsorption of the H+ ions.

Keywords

References

  1. Bull. Kor. Chem. Soc. v.19 Lee, S. H.;Choi, S. G.
  2. Bull. Kor. Chem. Soc. v.13 Moon, G. K.;Choi, S. G.;Kim, H. S.;Lee, S. H.
  3. Bull. Kor. Chem. Soc. v.14 Moon, G. K.;Choi, S. G.;Kim, H. S.;Lee, S. H.
  4. J. Phys. Chem. v.98 Lee, S. H.;Moon, G. K.;Choi, S. G.;Kim, H. S.
  5. Mol. Sim. v.17 Choi, S. G.;Lee, S. H.
  6. J. Phys. Chem. B v.101 Lee, S. H.;Choi, S. G.
  7. J. Am. Chem. Soc. v.102 Pluth, J. J.;Smith, J. V.
  8. J. Am. Chem. Soc. v.113 Nicholas, J. B.;Hopfinger, A. J.;Trouw, F. R.;Iton, L. X.
  9. J. Phys. Chem. B v.101 Faux, D. A.;Smith, W.;Forester, T. R.
  10. J. Phys. Chem. v.77 Yanagida, R. Y.;Amaro, A. A.;Seff, K.
  11. Proc. R. Soc. London v.A373 de Leeuw, S. W.;Perram, J. W.;Smith, E. R.
  12. Phys. Commun. v.25 Anastasiou, N.;Fincham, D.
  13. Zeolites v.8 Genechten, K. A. V.;Mortier, W. J.
  14. Comput. Phys. Commun. v.62 Chynoweth, S;Komp, U. C.;Scales, L. E.
  15. J. Reine. Angew. Math. v.Ⅳ Gauss, K. F.
  16. Numerical initial value problems in ordinary differential equation Gear, C. W.
  17. J. Phys. Chem. v.92 Shin, J. M.;No, K. T.;Jhon, M. S.
  18. Thermal vibrations in Crystallography Willis, B. T. M.;Pryor, A. W.
  19. Thermal Ellipsoid Plot Program; ORNL-3794 ORTEP: A FORTRAN Johnson, C. K.
  20. J. Chem. Phys. v.74 Behrens, P. H.;Wilson, K. R.
  21. Bull. Kor. Chem. Soc. Lee, S. H.;Choi, S. G.