2008年
ESR study of molecular dynamics and orientation of TEMPO included in organic 1-D nanochannel
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
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- 巻
- 10
- 号
- 9
- 開始ページ
- 1263
- 終了ページ
- 1269
- 記述言語
- 英語
- 掲載種別
- DOI
- 10.1039/b710098a
- 出版者・発行元
- ROYAL SOC CHEMISTRY
A mixture of 2,2,6,6-tetramethyl-1-piperidinyloxyl (TEMPO) radical and 2,2,6,6-tetramethyl-1-piperidine (TEMP) was included into organic 1-D nanochannels of tris(o-phenylenedioxy) cyclotriphosphazene (TPP) crystal. Dilution of the paramagnetic TEMPO radical was achieved with excess TEMP, thereby isolating a TEMPO molecule in the nanochannel. For inclusion compounds of TPP with TEMPO and TEMP (TEMPO/all guest compounds = 0.017 (1), and 0.15 (2)), temperature-dependent electron spin resonance (ESR) spectra were observed to investigate their molecular dynamics and orientation. In the temperature range from 112 K to room temperature, the spectra depended remarkably on the temperature. Temperature dependence was well interpreted by uniaxial rotation, suggesting that TEMPO molecules undergo uniaxial rotation about a channel axis with a molecular orientation in which the N-O bond in the nitroxide group is perpendicular to the channel axis. The activation energy of uniaxial rotation was evaluated as 4.5 +/- 0.3 kJ mol(-1).
- リンク情報
- ID情報
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- DOI : 10.1039/b710098a
- ISSN : 1463-9076
- eISSN : 1463-9084
- Web of Science ID : WOS:000253360900005