Hydration of ionic surfactant micelles from water oxygen-17 magnetic relaxation
Halle, Bertil LU and Carlström, Göran LU
(1981)
In Journal of Physical Chemistry
85(14).
p.2142-2147
- Abstract
Water oxygen-17 relaxation rates have been measured for aqueous solutions of micelles composed of ionic surfactants of varying alkyl chain length, head group, and counterion. The concentration of surfactant and salt was also varied. From these measurements, supplemented with relaxation data for short-chain molecules and with quadrupolar splittings from anisotropic mesophases, we derive structural and dynamic information about the molecular details of the water-micelle interaction. Water molecules at the micelle surface reorient anisotropically, typically 2-3 times slower than in pure water. The average lifetime for water molecules associated with sodium dodecyl sulfate micelles is 6-37 ns. The water-hydrocarbon contact in the micellar... (More)
Water oxygen-17 relaxation rates have been measured for aqueous solutions of micelles composed of ionic surfactants of varying alkyl chain length, head group, and counterion. The concentration of surfactant and salt was also varied. From these measurements, supplemented with relaxation data for short-chain molecules and with quadrupolar splittings from anisotropic mesophases, we derive structural and dynamic information about the molecular details of the water-micelle interaction. Water molecules at the micelle surface reorient anisotropically, typically 2-3 times slower than in pure water. The average lifetime for water molecules associated with sodium dodecyl sulfate micelles is 6-37 ns. The water-hydrocarbon contact in the micellar solutions is equivalent to less than two fully exposed methylene groups per amphiphile. Small head groups and small counterions produce the largest effects on the 17O relaxation rate, as expected from geometrical and electrostatic considerations.
(Less)
- author
- Halle, Bertil
LU
and Carlström, Göran
LU
- organization
- publishing date
- 1981-01-01
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Journal of Physical Chemistry
- volume
- 85
- issue
- 14
- pages
- 6 pages
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- scopus:33845557929
- ISSN
- 0022-3654
- DOI
- 10.1021/j150614a037
- language
- English
- LU publication?
- yes
- id
- 562d138f-a141-4634-a564-84c5d35d940f
- date added to LUP
- 2019-01-16 13:45:40
- date last changed
- 2022-03-29 02:34:14
@article{562d138f-a141-4634-a564-84c5d35d940f,
abstract = {{<p>Water oxygen-17 relaxation rates have been measured for aqueous solutions of micelles composed of ionic surfactants of varying alkyl chain length, head group, and counterion. The concentration of surfactant and salt was also varied. From these measurements, supplemented with relaxation data for short-chain molecules and with quadrupolar splittings from anisotropic mesophases, we derive structural and dynamic information about the molecular details of the water-micelle interaction. Water molecules at the micelle surface reorient anisotropically, typically 2-3 times slower than in pure water. The average lifetime for water molecules associated with sodium dodecyl sulfate micelles is 6-37 ns. The water-hydrocarbon contact in the micellar solutions is equivalent to less than two fully exposed methylene groups per amphiphile. Small head groups and small counterions produce the largest effects on the <sup>17</sup>O relaxation rate, as expected from geometrical and electrostatic considerations.</p>}},
author = {{Halle, Bertil and Carlström, Göran}},
issn = {{0022-3654}},
language = {{eng}},
month = {{01}},
number = {{14}},
pages = {{2142--2147}},
publisher = {{The American Chemical Society (ACS)}},
series = {{Journal of Physical Chemistry}},
title = {{Hydration of ionic surfactant micelles from water oxygen-17 magnetic relaxation}},
url = {{http://dx.doi.org/10.1021/j150614a037}},
doi = {{10.1021/j150614a037}},
volume = {{85}},
year = {{1981}},
}