Molecular Mechanics Studies on MFI Type Zeolites. 2. Isomorphous Substitution by Aluminium

1992 ◽  
Vol 57 (4) ◽  
pp. 681-686 ◽  
Author(s):  
Erik de Vos Burchart ◽  
Herman van Bekkum ◽  
Bastiaan van de Graaf
Keyword(s):  
Force Field ◽  
Molecular Mechanics ◽  
Mirror Symmetry ◽  
Organic Molecules ◽  
Unit Cell ◽  
Isomorphous Substitution ◽  
Zeolite Framework ◽  
Mm3 Force Field ◽  
Framework Energy

The molecular mechanics force field developed for all-silica structures is extended with parameters for tetrahedral aluminium. With this force field and the MM3 force field for organic molecules the effects of isomorphous substitution in the MFI framework are examined (4 Al/unit cell) with tetrapropyl ammonium (TPA) as the charge compensating cation. The results indicate a slight preference for the positions 2, 9, 5, 12, and 6 and the by mirror symmetry related positions. The differences in energy are mainly due to the differences in the zeolite framework energy.

Molecular Mechanics Studies on MFI Type Zeolites. 1. Effect of p-Xylene Adsorption on the Zeolite Structure

1992 ◽  
Vol 57 (4) ◽  
pp. 675-680 ◽  
Author(s):  
Erik de Vos Burchart ◽  
Bert van der Linden ◽  
Herman van Bekkum ◽  
Bastiaan van de Graaf
Keyword(s):  
Force Field ◽  
Molecular Mechanics ◽  
Organic Molecules ◽  
Monoclinic Space Group ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
Mechanics Model ◽  
Organic Zeolite ◽  
Molecular Mechanics Model ◽  
Mm3 Force Field

The effect of the adsorption of p-xylene on the all-silica MFI-structure is simulated with our molecular mechanics model. From experimental measurements it is known that the symmetry of the framework changes from monoclinic (space group P21/n.1.1.) towards orthorhombic (space group P212121) upon adsorption of p-xylene up to eight molecules per unit cell. The experimentally observed change in the geometry of the zeolite upon p-xylene adsorption is compared with that calculated by molecular mechanics. For the calculations our force field for all-silica zeolites is used in combination with the MM3 force field for organic molecules. Parameters for the organic-zeolite interactions are obtained by combination of the two force fields.

Molecular Mechanics (MM3*) Force Field Parameters for Calculations on Palladium Olefin Complexes with Phosphorus Ligands

1999 ◽  
Vol 18 (22) ◽  
pp. 4574-4583 ◽  
Author(s):  
Helena Hagelin ◽  
Mats Svensson ◽  
Björn Åkermark ◽  
Per-Ola Norrby
Keyword(s):  
Force Field ◽  
Molecular Mechanics ◽  
Phosphorus Ligands ◽  
Mm3 Force Field ◽  
Force Field Parameters

scholarly journals Anharmonic Molecular Mechanics: Ab Initio Based Morse Parametrizations for the Popular MM3 Force Field

2019 ◽  
Vol 123 (13) ◽  
pp. 2991-2999 ◽  
Author(s):  
R. J. Shannon ◽  
B. Hornung ◽  
D. P. Tew ◽  
D. R. Glowacki
Keyword(s):  
Force Field ◽  
Ab Initio ◽  
Molecular Mechanics ◽  
Mm3 Force Field

Molecular mechanics. The MM3 force field for alkenes

1990 ◽  
Vol 11 (7) ◽  
pp. 848-867 ◽  
Author(s):  
Norman L. Allinger ◽  
Fanbing Li ◽  
Liqun Yan
Keyword(s):  
Force Field ◽  
Molecular Mechanics ◽  
Mm3 Force Field

Molecular mechanics. The MM3 force field for hydrocarbons. 1

1989 ◽  
Vol 111 (23) ◽  
pp. 8551-8566 ◽  
Author(s):  
Norman L. Allinger ◽  
Young H. Yuh ◽  
Jenn Huei Lii
Keyword(s):  
Force Field ◽  
Molecular Mechanics ◽  
Mm3 Force Field
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