Gauche conformation of acyclic guest molecules appearing in the large cages of structure-H clathrate hydrates

Cited 10 time in webofscience Cited 10 time in scopus
  • Hit : 402
  • Download : 2
In the present study, measurements and analyses were made of the High-Power Decoupling (HPDEC) solid-state C-13 NMR spectra of structure-H (sH) methane hydrates with isopentane, one of the simplest and smallest acyclic large guest molecules, and methylcyclohexane (MCH), a commonly used cyclic guest molecule that is larger than isopentane. From the spectroscopic information, clear and definite evidence for the molecular conformation of acyclic guest molecules that are sufficiently small so as to be entrapped into the structure-H large cage (sH-L) was expected. The C-13 NMR chemical shift change was additionally checked through the use of a hydrogen-hydrogen steric perturbation model. From the overall results, we concluded that one of the smallest acyclic guest molecules, isopentane, participating in the formation of a structure-H clathrate hydrate is encaged, confirming the gauche conformation in large cavities. The present results strongly suggest that the guest position and structure in hydrate cages are greatly influenced by both short-range interactions between guest molecules and cage frameworks and long-range interactions between small and large guests. Accordingly, cage dynamics must be carefully considered when a specific sH hydrate is designed and synthesized for the purpose of tuning material properties.
Publisher
KOREAN INST CHEM ENGINEERS
Issue Date
2007-09
Language
English
Article Type
Article
Citation

KOREAN JOURNAL OF CHEMICAL ENGINEERING, v.24, no.5, pp.843 - 846

ISSN
0256-1115
DOI
10.1007/s11814-007-0051-5
URI
http://hdl.handle.net/10203/9476
Appears in Collection
CBE-Journal Papers(저널논문)
Files in This Item
This item is cited by other documents in WoS
⊙ Detail Information in WoSⓡ Click to see webofscience_button
⊙ Cited 10 items in WoS Click to see citing articles in records_button

qr_code

  • mendeley

    citeulike


rss_1.0 rss_2.0 atom_1.0