Brönsted and Lewis Acidity of the BF3/γ-Al2O3Alkylation Catalyst as Revealed by Solid-State NMR Spectroscopy and DFT Quantum Chemical Calculations

2005 ◽  
Vol 109 (27) ◽  
pp. 13124-13131 ◽  
Author(s):  
Jun Yang ◽  
Anmin Zheng ◽  
Mingjin Zhang ◽  
Qing Luo ◽  
Yong Yue ◽  
...  
Keyword(s):  
Solid State ◽  
Nmr Spectroscopy ◽  
Quantum Chemical Calculations ◽  
Solid State Nmr ◽  
Quantum Chemical ◽  
Lewis Acidity ◽  
Solid State Nmr Spectroscopy ◽  
Brønsted And Lewis Acidity

Characterisation of Germanium Monohalides by Solid-State NMR Spectroscopy and First Principles Quantum Chemical Calculations

2013 ◽  
Vol 66 (10) ◽  
pp. 1202 ◽  
Author(s):  
Margaret A. Hanson ◽  
Andreas Schnepf ◽  
Victor V. Terskikh ◽  
Yining Huang ◽  
Kim M. Baines
Keyword(s):  
Solid State ◽  
Nmr Spectroscopy ◽  
Quantum Chemical Calculations ◽  
First Principles ◽  
Solid State Nmr ◽  
Quantum Chemical ◽  
Solid State Nmr Spectroscopy ◽  
Amorphous Nature ◽  
Solid State Structures

Germanium(i) monohalides are useful starting materials to synthesise small, well defined germanium nanoclusters. However, due to the amorphous nature of solid GeBr and GeCl, details of their solid-state structures remain largely unknown. We investigate the arrangement within these novel binary materials using 35Cl, 79Br, and 73Ge solid-state NMR spectroscopy at 21.1 T and first principles quantum chemical calculations in order to suggest a possible model for the structure.

Probing the active sites for methane activation on Ga/ZSM-5 zeolites with solid-state NMR spectroscopy

2020 ◽  
Vol 56 (80) ◽  
pp. 12029-12032
Author(s):  
Xingling Zhao ◽  
Yueying Chu ◽  
Guodong Qi ◽  
Qiang Wang ◽  
Wei Gao ◽  
...  
Keyword(s):  
Solid State ◽  
Nmr Spectroscopy ◽  
Solid State Nmr ◽  
Active Sites ◽  
Acid Sites ◽  
Methane Activation ◽  
Lewis Acidity ◽  
Brønsted Acid Sites ◽  
Solid State Nmr Spectroscopy ◽  
Strong Lewis Acidity

Solid-state NMR reveals that the active Ga species are located on Brønsted acid sites in Ga/ZSM-5 zeolite channels and show strong Lewis acidity for methane activation.

scholarly journals A New Methodological Approach to Correlate Protective and Microscopic Properties by Soft X-ray Microscopy and Solid State NMR Spectroscopy: The Case of Cusa’s Stone

2021 ◽  
Vol 11 (13) ◽  
pp. 5767
Author(s):  
Veronica Ciaramitaro ◽  
Alberto Spinella ◽  
Francesco Armetta ◽  
Roberto Scaffaro ◽  
Emmanuel Fortunato Gulino ◽  
...  
Keyword(s):  
Solid State ◽  
Nmr Spectroscopy ◽  
Solid State Nmr ◽  
Methodological Approach ◽  
Polymer Chains ◽  
General Question ◽  
Protective Agent ◽  
Vapour Permeability ◽  
X Ray ◽  
Solid State Nmr Spectroscopy

Hydrophobic treatment is one of the most important interventions usually carried out for the conservation of stone artefacts and monuments. The study here reported aims to answer a general question about how two polymers confer different protective performance. Two fluorinated-based polymer formulates applied on samples of Cusa’s stone confer a different level of water repellence and water vapour permeability. The observed protection action is here explained on the basis of chemico-physical interactions. The distribution of the polymer in the pore network was investigated using scanning electron microscopy and X-ray microscopy. The interactions between the stone substrate and the protective agents were investigated by means of solid state NMR spectroscopy. The ss-NMR findings reveal no significant changes in the chemical neighbourhood of the observed nuclei of each protective agent when applied onto the stone surface and provide information on the changes in the organization and dynamics of the studied systems, as well as on the mobility of polymer chains. This allowed us to explain the different macroscopic behaviours provided by each protective agent to the stone substrate.

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