Abstract Oligomeric models of linear ladder silanes, siloxanes and siloxazanes with seven repeat units consisting of four-, six-, or eight-membered rings were designed and their conformations in chloroform were explored. The Low Mode–Monte Carlo conformational method was used to explore oligomeric flexibility on the OPLS-2005/GBSA(CHCl3) potential energy surface to obtain a set of low energy structures for each oligomer. These structures were then optimized using B3LYP/6-31G*/SCRF-PBF(CHCl3) calculations. The results indicate complex conformational dynamics with mostly non-planar, curved structures. Electron delocalization from the lone pair of electrons on N or O into empty 3d orbitals on Si was not observed.
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Machine-learning-assisted screening of pure-silica zeolites for effective removal of linear siloxanes and derivatives
As emerging organic contaminants, siloxanes have severe impacts on the environment and human health. Simple linear siloxanes and derivates, trimethylsilanol (TMS), dimethylsilanediol (DMSD), monomethylsilanetriol (MMST), and dimethylsulfone (DMSO 2 ), are four persistent and common problematic compounds (PCs) from the hydroxylation and sulfuration of polydimethylsiloxanes. Herein, through a two-step computational process, namely Grand Canonical Monte Carlo (GCMC) simulations and machine learning (ML), we systematically screened 50 959 hypothetical pure-silica zeolites and identified 230 preeminent zeolites with excellent adsorption performances with all these four linear siloxanes and derivates. This work vividly demonstrates that the collocation of data-driven science and computational chemistry can greatly accelerate materials discovery and help solve the most challenging separation problems in environmental science.
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- Award ID(s):
- 1849243
- PAR ID:
- 10158869
- Date Published:
- Journal Name:
- Journal of Materials Chemistry A
- Volume:
- 8
- Issue:
- 6
- ISSN:
- 2050-7488
- Page Range / eLocation ID:
- 3228 to 3237
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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