AI Article Synopsis
- - We used computational modeling based on Density Functional Theory to study how silanol nests form and how silicon can be replaced by titanium or aluminum in MSE-type frameworks, finding these processes are energetically favorable by over 100 kJ/mol.
- - We proposed a method to experimentally identify the position of titanium in Ti-MCM-68 zeolite by simulating infrared spectra from the adsorption of pyridine and acetonitrile.
- - Our modeling revealed that hydrogen peroxide prefers to adsorb molecularly at the titanium site rather than dissociatively, showing a preference of 20 to 40 kJ/mol regardless of whether there's a nearby titanium vacancy or not.
Article Abstract
We used computational modeling, based on Density Functional Theory, to help understand the preference for the formation of silanol nests and the substitution of Si by Ti or Al in different crystallographic positions of the MSE-type framework. All these processes were found to be energetically favorable by more than 100 kJ/mol. We suggested an approach for experimental identification of the T atom position in Ti-MCM-68 zeolite via simulation of infrared spectra of pyridine and acetonitrile adsorption at Ti. The modeling of adsorption of hydrogen peroxide at Ti center in the framework has shown that the molecular adsorption was preferred over the dissociative adsorption by 20 to 40 kJ/mol in the presence or absence of neighboring T-atom vacancy, respectively.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8659101 | PMC |
| http://dx.doi.org/10.3390/molecules26237296 | DOI Listing |
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