Dynamics of p-nitroaniline molecules in siliceous ZSM-5 studied by solid-state NMR

Sites and dynamics of p-nitroaniline (pNA) molecules in the micropores of siliceous ZSM-5 zeolite have been investigated by means of solid-state NMR. The adsorbed amounts of pNA studied were about 1.5, 4 and 6 molecules per unit cell of ZSM-5. 2H NMR and 13C NMR revealed that the motion of pNA was a 180° flip-flop around the C2 axis of the molecule when the adsorbed amount was less than four molecules per unit cell. The rate of the motion was about 50 kHz at 297 K, and the apparent activation energy was 57±17 kJ mol−1. 13C NMR confirmed the presence of different adsorbed states of pNA when the adsorbed amount was more than four molecules. Furthermore, 2H NMR revealed that the flip-flop motion of pNA was largely suppressed. These results indicate that the motion of pNA in the micropores of ZSM-5 depended on the adsorbed amount of pNA, and that the interaction between the guest molecules influenced the dynamics of the guest molecules.

[1]  C. Ratcliffe,et al.  The Interaction of Sorbates with Acid Sites in Zeolite Catalysts: A Powder Neutron Diffraction and 2H NMR Study of Benzene in H-SAPO-37 , 1995 .

[2]  A. Cheetham,et al.  Combined Neutron and X-ray Powder Diffraction Study of Zeolite Ca LSX and a 2H NMR Study of Its Complex with Benzene , 1995 .

[3]  H. Pfeifer,et al.  Deuterium nuclear magnetic resonance studies of the molecular dynamics of benzene in zeolites , 1988 .

[4]  J. Klinowski,et al.  Direct observation of shape selectivity in zeolite ZSM-5 by magic-angle-spinning NMR , 1989, Nature.

[5]  R. Vold,et al.  Deuterium quadrupole-echo NMR spectroscopy. III: Practical aspects of lineshape calculations for multiaxis rotational processes , 1987 .

[6]  M. Kennedy,et al.  A solid-state deuterium NMR study of internal rotation in p-nitroaniline , 1991 .

[7]  L. Gladden,et al.  Intercage and Intracage Transport of Aromatics in Zeolites NaY, HY, and USY Studied by 2H NMR , 1995 .

[8]  G. Maciel,et al.  Deuterium NMR Studies of Local Motions of Benzene Adsorbed on Ca-Montmorillonite , 1999 .

[9]  J. Newsam,et al.  Molecular motion of benzene, n-hexane, and cyclohexane in potassium zeolite L studied by deuterium NMR , 1989 .

[10]  Jürgen Caro,et al.  Optical second harmonic generation (SHG) on p-nitroaniline in large cyrstals of AIPO4-5 and ZSM-5 , 1992 .

[11]  G. Stucky,et al.  Inclusion tuning of nonlinear optical materials: switching the SHG of p-nitroaniline and 2-methyl-p-nitroaniline with molecular sieve hosts , 1988 .

[12]  D. Brouwer,et al.  Solid-state NMR and X-ray diffraction structural investigations of the p-nitroaniline/ZSM-5 complex , 2000 .

[13]  K. Kuroda,et al.  PHOTOFUNCTIONS OF INTERCALATION COMPOUNDS , 1995 .

[14]  A. Cheetham,et al.  Behavior of benzene in siliceous faujasite: a comparative study of deuteron NMR and molecular dynamics , 1993 .

[15]  R. Prins,et al.  Three-Dimensional Ordering of Molecules: p-Nitroaniline in Aligned ZSM-5 Single Crystals , 1997 .

[16]  H. Metiu,et al.  Behavior of Benzene in Na-X and Na-Y Zeolites: Comparative Study by 2H NMR and Molecular Mechanics , 1996 .

[17]  S. Hayashi.  NMR study of dynamics of dimethyl sulfoxide molecules in kaolinite/dimethyl sulfoxide intercalation compound , 1995 .

[18]  C. Dybowski,et al.  Investigation of methanol adsorbed on zeolite H-ZSM-5 by carbon-13 NMR spectrometry , 1990 .

[19]  K. Kunimori,et al.  13C and 1H MAS NMR Study of Benzene and p-Xylene in Zeolites and a Mesoporous Material FSM-16 , 1997 .

[20]  S. Hayashi.  NMR Study of Dynamics and Evolution of Guest Molecules in Kaolinite/Dimethyl Sulfoxide Intercalation Compound , 1997 .

[21]  H. Gies,et al.  Ordered and disordered pNA molecules in mesoporous MCM-41 , 1997 .

[22]  K. Hayamizu,et al.  High-resolution solid-state 13C NMR spectra of tetramethylammonium ions trapped in zeolites , 1985 .

[23]  Frank Marlow,et al.  Structure of Dipole Chains in an MFI Type Molecular Sieve , 1996 .

[24]  A. J. Vega,et al.  Deuterium solid-state NMR study of the dynamics of molecules sorbed by zeolites , 1986 .

[25]  A. L. V. Geet.  Calibration of methanol nuclear magnetic resonance thermometer at low temperature , 1970 .

[26]  Xiulan Xie,et al.  NMR Study of Kaolinite Intercalation Compounds with Formamide and Its Derivatives. 1. Structure and Orientation of Guest Molecules , 1999 .

[27]  Xiulan Xie,et al.  NMR STUDY OF KAOLINITE INTERCALATION COMPOUNDS WITH FORMAMIDE AND ITS DERIVATIVES. 2. DYNAMICS OF GUEST MOLECULES , 1999 .

[28]  P. Lacroix.  Organic Nonlinear Optical Chromophores in an Inorganic Environment. Toward an Interplay between Magnetism, Conductivity, and Nonlinear Optics , 2001 .

[29]  K. Kuroda,et al.  Intercalation of Nitroanilines into Kaolinite and Second Harmonic Generation , 2001 .