Abstract
We report here the results of our computational studies on porous catalysts to bring out the catalytic role played by nanostructures. We present two typical case studies where the molecular dynamic (MD) and quantum chemical (QC) techniques have revealed the important structural aspects involved in the functioning of nanostructured microporous materials. The central role played by the exchanged metal cations of zeolite A in the molecular sieving of nitrogen and oxygen was studied by MD calculations. The results indicated that the mobility of the exchanged cations which are dependent on temperature causes the separation of nitrogen and oxygen molecules. The real time visualization of the dynamic behavior of the exchanged cations during the MD process aids the understanding of this intriguing process occurring inside the micropores of the zeolites. The controlled pore opening of hydrated VPI-5 molecular sieve by careful removal of water leads to a large one dimensional channel. The possibility of anchoring organometallics, namely porphyrins with ‘enzyme-like’ active sites were studied using QC calculations. The analysis of the 3-d contours of electron density and molecular electrostatic potential maps corresponding to various porphyrin systems and the cluster models representing VPI-5 framework brought out the probable locations for porphyrins inside VPI-5.
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N.Y. Chen and T.F. Degnan, Chem. Eng. Prog., Feb., 32 (1988).
H. Hamada, Y. Kintaichi, T. Yoshinari, M. Tabata, M. Sasaki, and T. Ita, Catal. Today, 17, 111. (1993)
W. Holderich, M. Hesse, and F. Naumann, Angew. Chem. Int. Ed. Engl., 27 226 (1988).
R.V. Jasra, N.V. Choudary, and S.G.T. Bhat, Sep. Sci. Technol., 26 885. (1991)
G.A. Stucky, Science, 247 (1990) 669.
A. Miyamoto, T. Hattori, and T. Inui, Appl. Surface Sci., 60/61 660 (1992); A.. Miyamoto, R. Yamauchi, and M. Kubo, Appl. Surface Sci., 75 51 (1994).
A. Miyamoto, T. Hattori, and T. Inui, Physica C, 190 93 (1991).
A. Miyamoto, K. Takeichi, T. Hattori, M. Kubo, and T. Inui, Jpn. J. Appl. Phys., 31 4463 (1992).
A. Miyamoto, K. Matsuba, M. Kubo, K. Kawamura, and T. Inui, Chemistry Lett., 2055(1991); A.Miyamoto, M. Kubo, K. Matsuba, and T. Inui, In: Computer Aided Innovation of New Materials II, M. Doyama et al. (Eds.), p. 1025, Elsevier, Amsterdam, (1993); A. Miyamoto, K. Kagawa, M. Kubo, K. Matsuba, and T. Inui, ibid. 1993, p.1013.
P. Demontis, G.B. Suffiitti, S. Quartieri, E.S. Fois, and A. Gamba, Zeolites, 7 522 (1987).
P. Santikary, S. Yashonath, and G. Ananthakrishna, J. Phys. Chem., 96 10469 (1992) and references therein.
J.O. Titiloye, S.C. Parker, F.S. Stone, and C.R.A. Catlow, J. Phys. Chem., 95 4038 (1991) and references therein.
J.B. Nicholas, F.R. Trouw, J. E. Mertz, L.E.Iton, and A.J. Hopfinger, J. Phys. Chem., 97 4149 (1993) and references therein.
A. Miyamoto, H. Himei, Y. Oka, E. Maruya, M. Katagiri, R. Vetrivel, and M. Kubo, Catal. Today (in press).
A. Miyamoto, H. Himei, E. Maruya, M. Katagiri, R. Vetrivel, and M. Kubo, Proc. Int. Symp. Acid-Base Catalysis 11, Dec. 2–4, 1993, Sapporo, Japan (in press).
J. Sauer, Chem. Rev., 89 199. (1989)
S. Beran. In: Theoretical Aspects of Heterogeneous Catalysis, J.B. Moffat (Ed.), p. 160, van Nostrand Reinhold, New York, (1990).
E. Kassab, K. Seiti, and M. Allavena, J. Phys. Chem., 95 9425 (1991).
E.H. Teunissen, R.A. van Santen, A.P.J. Jansen, and F.B. van Duijneveldt, J. Phys. Chem., 97 203 (1993).
S. Prasad and R. Vetrivel, J. Phys. Chem., 98 1579 (1994).
K. Kawamura, in: Introduction to Molecular Simulations, I. Okada and E. Osawa (Eds.), Kaibun-do, Tokyo, 1989, Chapters 6 and 7.
W. Kohn and L.J. Sham, Phys. Rev., A140 1133 (1965).
B. Delley, J. Chem. Phys., 92 508 (1990).
M. Kubo and A. Miyamoto, in: Computer Aided Innovation of New Materials II”, M. Doyama et al. (Eds.), Elsevier, Amsterdam, 1993, p.295.
D.W. Breck and J.V. Smith: Sci. Amer. 200, 85 (1959).
L.B. McCusker, Ch. Baerlocher, E. Jahn, and M. Bulow: Zeolites 11, 308 (1991).
Y. W. Chan and R.B. Wilson, ACS Prep. Div. Petr. Chem., 33, 453 (1988).
R.F. Parton, L. Uytterhoeven, and P.A. Jacobs, Stud. Surface Sci. Catal., 59, 395 (1991).
M. Nakamura, T. Tatsumi, and H. Tominaga, Bull. Chem. Soc. Jpn., 63, 3334 (1990).
R. Parton, D. De Vos, and P.A. Jacobs. In: Zeolites Microporous Solids: Synthesis, Structure and Reactivity, E.G. Derouane et al. (Eds.), NATO ASI Ser. C, p. 555, Kluwer Academic Publishers, Amsterdam, (1992).
W.R. Scheidt, in: The Porphyrins, Vol. III, D. Dolphin (Ed.), Academic Press, 1978, p. 463.
J. Tornasi. In: Chemical Applications of Atomic and Molecular Electrostatic Potentials, P. Politzer and D.G. Truhlar (Eds.), p. 151, Plenum Press, New York, (1981).
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on leave from: National Chemical Laboratory, Pune - 411008, India
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Miyamoto, A., Katagiri, M., Kubo, M. et al. Computer assisted study of nanostructured microporous materials. Res. Chem. Intermed. 21, 151–166 (1995). https://doi.org/10.1163/156856795X00143
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DOI: https://doi.org/10.1163/156856795X00143