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Temperature effects on the C-H symmetric stretching vibrational frequencies of guest hydrocarbon molecules in 5¹², 5¹²6² and 5¹²6⁴ cages of sI and sII clathrate hydrates.

ABSTRACT: C-H symmetric stretching vibrational frequencies of CH₄, C₂H₄ and C₂H₆ molecules encapsulated in 5¹², 5¹²6² and 5¹²6⁴ cages of structures I (sI) and II (sII) clathrate hydrates measured by Raman spectroscopy in the temperature range of 93-183 K was analysed. The slopes of the symmetric stretch vibrational frequencies under changing temperatures (Δv/ΔT) for CH₄, C₂H₄ and C₂H₆ molecules encapsulated in sII 5¹²6⁴ cages were smaller than those for molecules in sI 5¹²6² cages, although sI 5¹²6² cages are smaller than sII 5¹²6⁴ cages. We compared the results of Δv/ΔT in this study with the geometrical properties of each host water cage, and these comparisons suggest that the geometry of host water cages affects Δv/ΔT.

SUBMITTER: Fuseya G

PROVIDER: S-EPMC9057130 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Temperature effects on the C-H symmetric stretching vibrational frequencies of guest hydrocarbon molecules in 512, 51262 and 51264 cages of sI and sII clathrate hydrates.

Fuseya Go G Takeya Satoshi S Hachikubo Akihiro A

RSC advances 20201012 61

C-H symmetric stretching vibrational frequencies of CH4, C2H4 and C2H6 molecules encapsulated in 512, 51262 and 51264 cages of structures I (sI) and II (sII) clathrate hydrates measured by Raman spectroscopy in the temperature range of 93-183 K was analysed. The slopes of the symmetric stretch vibrational frequencies under changing temperatures (Δv/ΔT) for CH4, C ...[more]

PMID: 35521261

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