caa a22 4500 606182322 CHVBK 20210128100815.0 cr unu---uuuuu 210128e20150301xx s 000 0 eng 10.1007/s10876-014-0839-5 doi (NATIONALLICENCE)springer-10.1007/s10876-014-0839-5 A DFT Exploration of the Adsorption of Methanol on the Brönsted Acid Site of Nanostructured H-ZSM-5 Catalyst: Probing the Effect of Cluster Size on the O-H···O Hydrogen Bond Based on NMR and NQR Parameters [Elektronische Daten] [Saeed Soltanali, Rouein Halladj, Fatemeh Ektefa] DFT calculations have been performed at the B3LYP/6-31++g** level to investigate the effectof the cluster size of ZSM-5 on the hydrogen atom of the Brönsted acid site via NQR and NMR parameters in methanol adsorption. ZSM-5 clusters have been modeled as 1T, 2T, 5T and 8T. T represents a general tetrahedral unit. Chemical shifts, δiso, of 1H atom in the Brönsted acid site as well as quadrupole coupling constant, CQ, and asymmetry parameter, ηQ, of 2H atom in the Brönsted acid site have been calculated. Spectrometric parameters showed that these parameters are influenced by the size and the shell of surrounding central T. Results indicate that inclusion of the next shell of T atoms (silicon atoms) around bridged hydroxyl group in the bare cluster models raises CQ and 1H δiso from 1T to 5T, 2T to 8T, while no significant changes are observed in the same electronic environment. The calculated the natural charge distribution of hydrogen atom in the Brönsted acid site analyzed by the NBO method for comparison of the cluster models. Springer Science+Business Media New York, 2015 DFT nationallicence H-ZSM-5 nationallicence Cluster size nationallicence Brönsted acid nationallicence NMR nationallicence NQR nationallicence Soltanali Saeed Department of Chemical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran aut Halladj Rouein Department of Chemical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran aut Ektefa Fatemeh Department of Chemistry, Tarbiat Modares University, Tehran, Iran aut Journal of Cluster Science Springer US; http://www.springer-ny.com 26/2(2015-03-01), 565-579 1040-7278 26:2<565 2015 26 10876 https://doi.org/10.1007/s10876-014-0839-5 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10876-014-0839-5 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Soltanali Saeed Department of Chemical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran aut NATIONALLICENCE 700 1- Halladj Rouein Department of Chemical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran aut NATIONALLICENCE 700 1- Ektefa Fatemeh Department of Chemistry, Tarbiat Modares University, Tehran, Iran aut NATIONALLICENCE 773 0- Journal of Cluster Science Springer US; http://www.springer-ny.com 26/2(2015-03-01), 565-579 1040-7278 26:2<565 2015 26 10876