TY - JOUR
T1 - A consistent molecular mechanics force field for aluminophosphates
AU - De Vos Burchart, Erik
AU - Van Bekkum, Herman
AU - Van De Graaf, Bastiaan
AU - Vogt, Eelco T C
PY - 1992/12/1
Y1 - 1992/12/1
N2 - A consistent molecular mechanics force field has been developed for aluminophosphate structures including berlinite and several molecular sieve structures, which predicts the geometry, heat of formation and the vibrational frequencies reasonably well. The force field consists of a bonding term, a bending term and long-range interactions. Charges are calculated using the electronegativity equalization method of Mortier et al. (W. J. Mortier, S. K. Ghoshand and S. Shankar, J. Am. Chem. Soc., 1986, 108, 4315), modified with the relative permittivity. The parameters for oxygen are transferable with the all-silica force field recently developed. Results are given for berlinite, AlPO-5 (AFI), AlPO-8 (AET), AlPO-11 (AEL), AlPO-18 (AEI), AlPO-25 (ATV), AlPO-35 (LEV), AlPO-37 (FAU) and VPI-5 (VFI), as well as for the hydrated structures of variscite and VPI-5 (six-fold coordination around aluminium) and the structures of AlPO-18 and AlPO-21 (ATO) with extra-framework oxygen (five-fold coordinated aluminium). Atomic positions of the AlPO-35 structure (both DLS and energy minimized), which have not been reported before, are also given.
AB - A consistent molecular mechanics force field has been developed for aluminophosphate structures including berlinite and several molecular sieve structures, which predicts the geometry, heat of formation and the vibrational frequencies reasonably well. The force field consists of a bonding term, a bending term and long-range interactions. Charges are calculated using the electronegativity equalization method of Mortier et al. (W. J. Mortier, S. K. Ghoshand and S. Shankar, J. Am. Chem. Soc., 1986, 108, 4315), modified with the relative permittivity. The parameters for oxygen are transferable with the all-silica force field recently developed. Results are given for berlinite, AlPO-5 (AFI), AlPO-8 (AET), AlPO-11 (AEL), AlPO-18 (AEI), AlPO-25 (ATV), AlPO-35 (LEV), AlPO-37 (FAU) and VPI-5 (VFI), as well as for the hydrated structures of variscite and VPI-5 (six-fold coordination around aluminium) and the structures of AlPO-18 and AlPO-21 (ATO) with extra-framework oxygen (five-fold coordinated aluminium). Atomic positions of the AlPO-35 structure (both DLS and energy minimized), which have not been reported before, are also given.
UR - http://www.scopus.com/inward/record.url?scp=0000506949&partnerID=8YFLogxK
U2 - 10.1039/FT9928802761
DO - 10.1039/FT9928802761
M3 - Article
AN - SCOPUS:0000506949
SN - 0956-5000
VL - 88
SP - 2761
EP - 2769
JO - Journal of the Chemical Society, Faraday Transactions
JF - Journal of the Chemical Society, Faraday Transactions
IS - 18
ER -