Ruth Riter - Academia.edu (original) (raw)
Papers by Ruth Riter
The Journal of Chemical Physics, Dec 7, 1998
Polar solvation dynamics of water sequestered inside Aerosol OT (AOT) reverse micelles have been ... more Polar solvation dynamics of water sequestered inside Aerosol OT (AOT) reverse micelles have been investigated as a function of the surfactant countercation, specifically replacing Na+ for K+ and Ca2+. For Ca-AOT reverse micelles, the solvation dynamics for the smallest micelles probed occurs on a subnanosecond time scale. The K-AOT reverse micelles display an additional ultrafast component that is attributable to bulklike water motion. As previously reported for Na-AOT reverse micelles [Riter, Willard, and Levinger, J. Phys. Chem. B 102, 2705 (1998)], solvent mobility increases with increasing micellar size for both Ca-AOT and K-AOT reverse micelles. The solvation dynamics in strongly ionic aqueous solutions of Ca2+ and K+ have also been investigated. The 10 M electrolyte solutions display water motion on significantly shorter time scales with substantial ultrafast components. These results show that the micellar interfacial structure plays a significant role in immobilizing intramicellar water and that solvent immobilization in the reverse micelles is not merely a result of solvent-ion interactions.
Qels 97 Summaries of Papers Presented at the Quantum Electronics and Laser Science Conference, May 18, 1997
The Journal of Physical Chemistry, 1995
Page 1. Physical Chemistry The Journal of 0 Copyright 1995 by the American Chemical Society VOLUM... more Page 1. Physical Chemistry The Journal of 0 Copyright 1995 by the American Chemical Society VOLUME 99, NUMBER 43, OCTOBER 26,1995 LETTERS Evidence for Coherent Energy Transfer in Allophycocyanin Trimers Maurice ...
Springer Series in Chemical Physics, 1996
The Journal of Physical Chemistry, 1995
Page 1. Physical Chemistry The Journal of 0 Copyright 1995 by the American Chemical Society VOLUM... more Page 1. Physical Chemistry The Journal of 0 Copyright 1995 by the American Chemical Society VOLUME 99, NUMBER 43, OCTOBER 26,1995 LETTERS Evidence for Coherent Energy Transfer in Allophycocyanin Trimers Maurice ...
The Journal of Physical Chemistry, 1996
The Journal of Physical Chemistry B, 1997
The Journal of Physical Chemistry B, 2004
ABSTRACT
The Journal of Physical Chemistry B, 1998
... 70 attributed the slower dynamics to the dipolar nature of the probe molecules. They base thi... more ... 70 attributed the slower dynamics to the dipolar nature of the probe molecules. They base this result on recent computer simulations performed by Nandi et al. ... However, Nandi et al. 71 calculated a tcf for bulk water that agrees well with that reported by Jimenez et al. ...
The Journal of Physical Chemistry B, 1997
... 19) Chhabra, V.; Lal, M.; Maitra, AN J. Mater. Res. 1995, 10, 2689−2692. ...
The Journal of Physical Chemistry B, 1998
ABSTRACT
The Journal of Physical Chemistry B, 1997
Physical Review Letters, 2005
The dynamics of water, confined on a nanometer length scale (1.7 to 4.0 nm) in sodium bis-(2ethyl... more The dynamics of water, confined on a nanometer length scale (1.7 to 4.0 nm) in sodium bis-(2ethylhexyl) sulfosuccinate reverse micelles, is directly investigated using frequency resolved infrared vibrational echo experiments. The data are compared to bulk water and salt solution data. The experimentally determined frequency-frequency correlation functions show that the confined water dynamics is substantially slower than bulk water dynamics and is size dependent. The fastest dynamics (50 fs) is more similar to bulk water, while the slowest time scale dynamics is much slower than water, and, in analogy to bulk water, reflects the making and breaking of hydrogen bonds.
Journal of the American Chemical Society, 1998
... Ruth E. Riter, Erik P. Undiks, and Nancy E. Levinger*. Contribution from the Department of Ch... more ... Ruth E. Riter, Erik P. Undiks, and Nancy E. Levinger*. Contribution from the Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872. J. Am. Chem. Soc. , 1998, 120 (24), pp 6062–6067. DOI: 10.1021 ...
Journal of the American Chemical Society, 1998
ABSTRACT The solvation dynamics of water in lecithin/cyclohexane reverse micelles have been deter... more ABSTRACT The solvation dynamics of water in lecithin/cyclohexane reverse micelles have been determined via ultrafast time-resolved fluorescence studies. At hydration levels w0 ≤ 4.8, the reverse micellar samples are nonviscous. Here a single relaxation time is observed that is much longer than the response of free or bulk water. In contrast, small additions of water to the samples produces a viscous gel, referred to by others as an organogel or “living polymer”. At hydration levels of w0 ≥ 5.8, three relaxation times are observed with approximate time constants of 0.5, 15, and 200 ps, the shortest of which correlates to free water motion. The dynamics reveal no evidence of micelle crossover or branch points associated with gel formation. In comparison to Aerosol OT reverse micelles of similar hydration, the water in the lecithin reverse micelles is significantly more restricted. It is proposed that lecithin sequesters significantly more water than previously predicted precluding formation of distinct core water pools in the micelles. The results are also compared to models for aqueous structure and dynamics near phospholipid membranes and to bulk water dynamics.
The Journal of Chemical Physics, 1998
[The Journal of Chemical Physics 109, 9995 (1998)]. Debi Pant, Ruth E. Riter, Nancy E. Levinger. ... more [The Journal of Chemical Physics 109, 9995 (1998)]. Debi Pant, Ruth E. Riter, Nancy E. Levinger. Abstract. ... Colloid Interface Sci. 59, 95 (1995). J. Eastoe, G. Frangneto, BH Robinson, TF Towey, RK Heenan, and FJ Leng, J. Chem. Soc., Faraday Trans. 88, 461 (1992). ...
Chemosphere, 1990
... ON THE SENSITIZED PHOTOOXIDATION OF BROMACIL Ruth E. Riter, V. Dean Adams, Dennis B. George&a... more ... ON THE SENSITIZED PHOTOOXIDATION OF BROMACIL Ruth E. Riter, V. Dean Adams, Dennis B. George', Eugene A. Kline The Center for ... lifetime of the excited triplet state of rose bengal than either methylene blue or riboflavin (Gollnic and Schenck, 1964; Denny and Nickon ...
Chemical Reviews, 2012
ABSTRACT The self-assembly of amphiphiles in the absence of water is studied. The assembly of amp... more ABSTRACT The self-assembly of amphiphiles in the absence of water is studied. The assembly of amphiphiles into microemulsions and reverse micelles in nonpolar solvents while sequestering a polar nonaqueous core is discussed. Fletcher et al. used dynamic light scattering (DLS) and viscosimetry to study thermodynamically stable AOT stabilized dispersions of GY in n-heptane. Sarkar and co-workers have probed GY/AOT/isooctane reverse micelles through steady-state and time-resolved fluorescence spectroscopy of two solvatochromic dyes, coumarin 480 and coumarin 490. Martino and Kaler reported the effect on microemulsion phase behavior and microstructure occurring when replacing water with PG, GY, and their mixtures in systems made with the nonionic surfactants pentaethylene glycol mono-n-decyl ether (C10E5). Mehta et al. have explored phase diagrams for several nonaqueous polar solvents in AOT/hexane.
Chemical Physics Letters, 1997
... CHEMICAL PHYSICS LETTERS Radiationless decay from the ligand-to-metal charge-transfer state i... more ... CHEMICAL PHYSICS LETTERS Radiationless decay from the ligand-to-metal charge-transfer state in the blue copper protein plastocyanin Maurice D. Edington, William M. Diffey, William J. Doria, Ruth E. Riter 1, Warren F. Beck ... 33] DS Alavi, RS Hartman, DH Waldeck, J. Chem. ...
The Journal of Chemical Physics, Dec 7, 1998
Polar solvation dynamics of water sequestered inside Aerosol OT (AOT) reverse micelles have been ... more Polar solvation dynamics of water sequestered inside Aerosol OT (AOT) reverse micelles have been investigated as a function of the surfactant countercation, specifically replacing Na+ for K+ and Ca2+. For Ca-AOT reverse micelles, the solvation dynamics for the smallest micelles probed occurs on a subnanosecond time scale. The K-AOT reverse micelles display an additional ultrafast component that is attributable to bulklike water motion. As previously reported for Na-AOT reverse micelles [Riter, Willard, and Levinger, J. Phys. Chem. B 102, 2705 (1998)], solvent mobility increases with increasing micellar size for both Ca-AOT and K-AOT reverse micelles. The solvation dynamics in strongly ionic aqueous solutions of Ca2+ and K+ have also been investigated. The 10 M electrolyte solutions display water motion on significantly shorter time scales with substantial ultrafast components. These results show that the micellar interfacial structure plays a significant role in immobilizing intramicellar water and that solvent immobilization in the reverse micelles is not merely a result of solvent-ion interactions.
Qels 97 Summaries of Papers Presented at the Quantum Electronics and Laser Science Conference, May 18, 1997
The Journal of Physical Chemistry, 1995
Page 1. Physical Chemistry The Journal of 0 Copyright 1995 by the American Chemical Society VOLUM... more Page 1. Physical Chemistry The Journal of 0 Copyright 1995 by the American Chemical Society VOLUME 99, NUMBER 43, OCTOBER 26,1995 LETTERS Evidence for Coherent Energy Transfer in Allophycocyanin Trimers Maurice ...
Springer Series in Chemical Physics, 1996
The Journal of Physical Chemistry, 1995
Page 1. Physical Chemistry The Journal of 0 Copyright 1995 by the American Chemical Society VOLUM... more Page 1. Physical Chemistry The Journal of 0 Copyright 1995 by the American Chemical Society VOLUME 99, NUMBER 43, OCTOBER 26,1995 LETTERS Evidence for Coherent Energy Transfer in Allophycocyanin Trimers Maurice ...
The Journal of Physical Chemistry, 1996
The Journal of Physical Chemistry B, 1997
The Journal of Physical Chemistry B, 2004
ABSTRACT
The Journal of Physical Chemistry B, 1998
... 70 attributed the slower dynamics to the dipolar nature of the probe molecules. They base thi... more ... 70 attributed the slower dynamics to the dipolar nature of the probe molecules. They base this result on recent computer simulations performed by Nandi et al. ... However, Nandi et al. 71 calculated a tcf for bulk water that agrees well with that reported by Jimenez et al. ...
The Journal of Physical Chemistry B, 1997
... 19) Chhabra, V.; Lal, M.; Maitra, AN J. Mater. Res. 1995, 10, 2689−2692. ...
The Journal of Physical Chemistry B, 1998
ABSTRACT
The Journal of Physical Chemistry B, 1997
Physical Review Letters, 2005
The dynamics of water, confined on a nanometer length scale (1.7 to 4.0 nm) in sodium bis-(2ethyl... more The dynamics of water, confined on a nanometer length scale (1.7 to 4.0 nm) in sodium bis-(2ethylhexyl) sulfosuccinate reverse micelles, is directly investigated using frequency resolved infrared vibrational echo experiments. The data are compared to bulk water and salt solution data. The experimentally determined frequency-frequency correlation functions show that the confined water dynamics is substantially slower than bulk water dynamics and is size dependent. The fastest dynamics (50 fs) is more similar to bulk water, while the slowest time scale dynamics is much slower than water, and, in analogy to bulk water, reflects the making and breaking of hydrogen bonds.
Journal of the American Chemical Society, 1998
... Ruth E. Riter, Erik P. Undiks, and Nancy E. Levinger*. Contribution from the Department of Ch... more ... Ruth E. Riter, Erik P. Undiks, and Nancy E. Levinger*. Contribution from the Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872. J. Am. Chem. Soc. , 1998, 120 (24), pp 6062–6067. DOI: 10.1021 ...
Journal of the American Chemical Society, 1998
ABSTRACT The solvation dynamics of water in lecithin/cyclohexane reverse micelles have been deter... more ABSTRACT The solvation dynamics of water in lecithin/cyclohexane reverse micelles have been determined via ultrafast time-resolved fluorescence studies. At hydration levels w0 ≤ 4.8, the reverse micellar samples are nonviscous. Here a single relaxation time is observed that is much longer than the response of free or bulk water. In contrast, small additions of water to the samples produces a viscous gel, referred to by others as an organogel or “living polymer”. At hydration levels of w0 ≥ 5.8, three relaxation times are observed with approximate time constants of 0.5, 15, and 200 ps, the shortest of which correlates to free water motion. The dynamics reveal no evidence of micelle crossover or branch points associated with gel formation. In comparison to Aerosol OT reverse micelles of similar hydration, the water in the lecithin reverse micelles is significantly more restricted. It is proposed that lecithin sequesters significantly more water than previously predicted precluding formation of distinct core water pools in the micelles. The results are also compared to models for aqueous structure and dynamics near phospholipid membranes and to bulk water dynamics.
The Journal of Chemical Physics, 1998
[The Journal of Chemical Physics 109, 9995 (1998)]. Debi Pant, Ruth E. Riter, Nancy E. Levinger. ... more [The Journal of Chemical Physics 109, 9995 (1998)]. Debi Pant, Ruth E. Riter, Nancy E. Levinger. Abstract. ... Colloid Interface Sci. 59, 95 (1995). J. Eastoe, G. Frangneto, BH Robinson, TF Towey, RK Heenan, and FJ Leng, J. Chem. Soc., Faraday Trans. 88, 461 (1992). ...
Chemosphere, 1990
... ON THE SENSITIZED PHOTOOXIDATION OF BROMACIL Ruth E. Riter, V. Dean Adams, Dennis B. George&a... more ... ON THE SENSITIZED PHOTOOXIDATION OF BROMACIL Ruth E. Riter, V. Dean Adams, Dennis B. George', Eugene A. Kline The Center for ... lifetime of the excited triplet state of rose bengal than either methylene blue or riboflavin (Gollnic and Schenck, 1964; Denny and Nickon ...
Chemical Reviews, 2012
ABSTRACT The self-assembly of amphiphiles in the absence of water is studied. The assembly of amp... more ABSTRACT The self-assembly of amphiphiles in the absence of water is studied. The assembly of amphiphiles into microemulsions and reverse micelles in nonpolar solvents while sequestering a polar nonaqueous core is discussed. Fletcher et al. used dynamic light scattering (DLS) and viscosimetry to study thermodynamically stable AOT stabilized dispersions of GY in n-heptane. Sarkar and co-workers have probed GY/AOT/isooctane reverse micelles through steady-state and time-resolved fluorescence spectroscopy of two solvatochromic dyes, coumarin 480 and coumarin 490. Martino and Kaler reported the effect on microemulsion phase behavior and microstructure occurring when replacing water with PG, GY, and their mixtures in systems made with the nonionic surfactants pentaethylene glycol mono-n-decyl ether (C10E5). Mehta et al. have explored phase diagrams for several nonaqueous polar solvents in AOT/hexane.
Chemical Physics Letters, 1997
... CHEMICAL PHYSICS LETTERS Radiationless decay from the ligand-to-metal charge-transfer state i... more ... CHEMICAL PHYSICS LETTERS Radiationless decay from the ligand-to-metal charge-transfer state in the blue copper protein plastocyanin Maurice D. Edington, William M. Diffey, William J. Doria, Ruth E. Riter 1, Warren F. Beck ... 33] DS Alavi, RS Hartman, DH Waldeck, J. Chem. ...