Hydrodynamic Interpretation on the Rotational Diffusion of Peroxylamine Disulfonate Solute Dissolved in Room Temperature Ionic Liquids As Studied by Electron Paramagnetic Resonance Spectroscopy

Miyake, Yusuke; Akai, Nobuyuki; Kawai, Akio; Shibuya, Kazuhiko

doi:10.1021/jp112151d

Cited by 23 publications

(17 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Additional reasons behind the faster rotation about the molecular x -axis could be (i) the electrostatic interaction of the ammonium group (−N(CH 3 ) 3 + ) at the 4-position of the spin probe with the BF 4 – anion in RTIL and (ii) the hydrogen bonding between the nitroxide group of Cat-1 and the acidic imidazolium protons . Such reasoning is in accordance with the measured rotational anisotropy of PADS (potassium peroxylamine disulfonate) probe in RTILs . This probe contains two negatively charged sulfonyl groups and exhibits more substantial anisotropy in RTILs ( N = 3–5) than Cat-1.…”

Section: Resultssupporting

confidence: 62%

“…These findings suggest that rotational anisotropy of PADS in RTILs is strongly influenced by the Coulombic interaction between the sulfonyl groups and the RTIL cations. 55 The change in N as a function of C (Figure 6a and Table 3), very possibly, reflects the transition between the homogeneously globular structure and the spongelike structure, Figure 11 in ref 53, which happens at C 4 , that is, in BmimBF 4 .…”

Section: ■ Methodsmentioning

confidence: 88%

“…15 Such reasoning is in accordance with the measured rotational anisotropy of PADS (potassium peroxylamine disulfonate) probe in RTILs. 55 This probe contains two negatively charged sulfonyl groups and exhibits more substantial anisotropy in RTILs (N = 3−5) than Cat-1. The N values of PADS in RTILs were found to be larger than the value N = 2.4 of PADS in organic solvent Nmethylimidazole and the theoretical value N = 1.4 calculated from the prolate shape of PADS.…”

Section: ■ Methodsmentioning

confidence: 99%

See 2 more Smart Citations

Rotation of a Charged Spin Probe in Room-Temperature Ionic Liquids

et al. 2021

View full text Add to dashboard Cite

X-band electron paramagnetic resonance spectroscopy has been used to investigate the rotational diffusion of a stable, positively charged nitroxide 4-trimethylammonium-2,2,6,6-tetramethylpiperidine-1-oxyl iodide (Cat-1) in a series of 1-alkyl-3methylimidazolium tetrafluoroborate room-temperature ionic liquids (RTILs) having alkyl chain lengths from two to eight carbons. The rotation of Cat-1 is anisotropic with the preferential axis of rotation along the NO • moiety. The Stokes−Einstein−Debye law describes the mean rotational correlation time of Cat-1, assuming that the hydrodynamic radius is smaller than the van der Waals radius of the probe. This implies that the probe rotates freely, experiencing slip boundary condition, which is solvent-dependent. The rotational correlation time of Cat-1 in RTILs can very well be fitted to a power-law functionality with a singular temperature, which suggests that the apparent activation energy of rotation exhibits non-Arrhenius behavior. Compared to the rotation of perdeuterated 2,2,6,6-tetramethyl-4-oxopiperidine-1-oxyl (pDTO), which is neutral, the rotation of Cat-1 is several times slower. The rotational anisotropy, the ratio of the rotational times of pDTO and Cat-1, and the apparent activation energy indicate the transition from a homogeneously globular structure to a spongelike structure when the alkyl chain has four carbons, which is also observed in molecular dynamics computational studies. For the first time, we have been able to show that the rotational correlation time of a solute molecule can be analyzed in terms of the Cohen−Turnbull free volume theory. The Cohen−Turnbull theory fully describes the rotation of Cat-1 in all ionic liquids in the measured temperature range.

show abstract

Section: Resultssupporting

confidence: 62%

Section: ■ Methodsmentioning

confidence: 88%

Section: ■ Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Rotation of a Charged Spin Probe in Room-Temperature Ionic Liquids

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Rotational motion of spin probes in imidazolium-based ionic liquids has been reported by Sengupta and Miyake as well. 35 − 37 …”

Section: Introductionmentioning

confidence: 99%

High-Pressure ESR Spectroscopy: On the Rotational Motion of Spin Probes in Pressurized Ionic Liquids

Kattnig

Grampp

2022

J. Phys. Chem. B

View full text Add to dashboard Cite

We report high-pressure (up to 50 MPa) ESR-spectroscopic investigations on the rotational correlation times of the nitroxide radicals 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO), 4-hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPOL), and 4-amino-2,2,6,6-tetramethylpiperidine 1-oxyl (ATEMPO) in the ionic liquids 1-ethyl-3-methylimidazolium tetrafluoroborate (emimBF 4 ), 1-butyl-3-methylimidazolium hexafluorophosphate (bmimPF 6 ), 1-butyl-3-methylimidazolium tetrafluoroborate (bmimBF 4 ), 1-methyl-3-octylimidazolium tetrafluoroborate (omimBF 4 ), and 1-methyl-3-octylimidazolium hexafluorophosphate (omimPF 6 ). The activation volumes (38.5–56.6 Å 3 ) determined from pressure dependent rotational diffusion coefficients agree well with the pressure dependent viscosities of the ionic liquids. Experimentally, the fractional exponent of the generalized Stokes–Einstein–Debye relation is found to be close to one.

show abstract

“…Ionic liquids (ILs), which are a group of organic salts with melting point close to or below room temperature, have been studied extensively in recent years. They have many unique physicochemical characteristics, such as negligible vapor pressure, good thermal stability, relatively high ionic conductivity and, especially, the designable properties . ILs have successfully been applied to various areas, such as replacing conventional organic solvent in organic or inorganic synthesis, electrochemical reactions, stationary phases in GC, and mobile phases additive in HPLC .…”

Section: Introductionmentioning

confidence: 99%

Tetramethylammonium‐lactobionate: A novel ionic liquid chiral selector based on saccharides in capillary electrophoresis

Zhang

et al. 2015

Electrophoresis

View full text Add to dashboard Cite

Chiral ionic liquids (ILs) have aroused widespread interest in separation science; however, only a few papers have reported the application of chiral ILs in CE for enantioseparation, and the use of chiral ILs as the sole chiral selector in an electrophoretic or a chromatographic system was reported in only three papers. In this study, we designed a lactobionic acid LA-based IL, tetramethylammonium-lactobionate (TMA-LA), and it is very interesting to find that the chiral separation capability can be remarkably improved when a conventional saccharide chiral selector evolved into an IL chiral selector. A comparative study of the enantiorecognition capability of three separation systems (single LA system, LA + TMA-chloride (TMA-Cl) system, and TMA-LA IL system) was also conducted, and the results showed that the use of TMA-LA IL as the sole chiral selector exhibited a remarkable superiority. A series of parameters affecting the enantioseparation, such as the type and proportion of organic modifier, buffer composition and pH, chiral selector concentration, as well as applied voltage were systematically investigated. The best enantioseparation was obtained at pH 7.6 using a 40 mM borax buffer with 40% v/v methanol, 200 mM TMA-LA, and 20 kV applied voltage. It is the first time that a saccharide-based IL is evaluated as a sole chiral selector in CE, and we hope this study would provide a new direction for the development of novel ILs chiral selectors based on conventional chiral selectors.

show abstract

Hydrodynamic Interpretation on the Rotational Diffusion of Peroxylamine Disulfonate Solute Dissolved in Room Temperature Ionic Liquids As Studied by Electron Paramagnetic Resonance Spectroscopy

Cited by 23 publications

References 51 publications

Rotation of a Charged Spin Probe in Room-Temperature Ionic Liquids

Rotation of a Charged Spin Probe in Room-Temperature Ionic Liquids

High-Pressure ESR Spectroscopy: On the Rotational Motion of Spin Probes in Pressurized Ionic Liquids

Tetramethylammonium‐lactobionate: A novel ionic liquid chiral selector based on saccharides in capillary electrophoresis

Contact Info

Product

Resources

About