TY - JOUR
T1 - Cu-MCM-22 zeolite
T2 - A combined X-ray powder diffraction and computational study of the local structure of extra-framework copper ions
AU - Milanesio, M.
AU - Croce, G.
AU - Frache, A.
AU - Mascarenhas, A. J.S.
AU - Oliveira, E. C.
PY - 2005
Y1 - 2005
N2 - Local structure and site distribution of extra-framework copper ions in Cu-exchanged MCM-22 zeolite have been determined by synchrotron radiation X-ray powder diffraction analysis combined with ab-initio molecular orbital (DFT) calculations. Three Cu sites (SI, SuII and S III) in 6-membered rings and one site (SVI) in a 5-membered ring close to the inter lamellar region, were located inside the MCM-22 supercage, whereas no Cu ions were found within the sinusoidal channels. The existence of two families of Cu sites (in 5- and 6-membered rings respectively) with different steric hindrance and adsorptive capacity, as indicated by previous FTIR study of adsorbed NO [A. Frache, et al., Langmuir, 18 (2002) 6875], was fully confirmed in this study.
AB - Local structure and site distribution of extra-framework copper ions in Cu-exchanged MCM-22 zeolite have been determined by synchrotron radiation X-ray powder diffraction analysis combined with ab-initio molecular orbital (DFT) calculations. Three Cu sites (SI, SuII and S III) in 6-membered rings and one site (SVI) in a 5-membered ring close to the inter lamellar region, were located inside the MCM-22 supercage, whereas no Cu ions were found within the sinusoidal channels. The existence of two families of Cu sites (in 5- and 6-membered rings respectively) with different steric hindrance and adsorptive capacity, as indicated by previous FTIR study of adsorbed NO [A. Frache, et al., Langmuir, 18 (2002) 6875], was fully confirmed in this study.
KW - Ab-initio Calculations
KW - Copper Location
KW - Extra-Framework Sites
KW - MCM-22 zeolite
KW - MWW
KW - Synchrotron Radiation
KW - X-ray Powder Diffraction
UR - http://www.scopus.com/inward/record.url?scp=21244503161&partnerID=8YFLogxK
U2 - 10.1016/s0167-2991(05)80169-7
DO - 10.1016/s0167-2991(05)80169-7
M3 - Article
SN - 0167-2991
VL - 155
SP - 415
EP - 426
JO - Studies in Surface Science and Catalysis
JF - Studies in Surface Science and Catalysis
ER -