Solvent Isotopic Effects on a Surfactant Headgroup at the Air-Liquid Interface

Uvinduni I. Premadasa; Negar Moradighadi; Kondalarao Kotturi; Jeeranan Nonkumwong; Md Rubel Khan; Marc Singer; Eric Masson; Katherine L.A. Cimatu

doi:10.1021/acs.jpcc.8b03680

Solvent Isotopic Effects on a Surfactant Headgroup at the Air-Liquid Interface

Uvinduni I. Premadasa, Negar Moradighadi, Kondalarao Kotturi, Jeeranan Nonkumwong, Md Rubel Khan, Marc Singer, Eric Masson, Katherine L.A. Cimatu

Research output: Contribution to journal › Article › peer-review

20 Scopus citations

Abstract

The geometry, arrangement, and orientation of a quaternary ammonium surfactant flanked by two methyl groups, a benzyl head, and an octyl tail were assessed at the air-water and air-deuterium oxide (D₂O) interfaces using sum frequency generation vibrational spectroscopy. Remarkably, symmetric and asymmetric N-CH₃ stretches (at ∼2979 and ∼3045 cm^-1, respectively, in the SSP polarization combination) were visible in water but negligible in deuterium oxide. We concluded that D₂O addition triggers the average reorientation of the dimethyl amino units parallel to the interface and possibly changes the overall conformation of the surfactant. A reduced number of gauche defects in the surfactant octyl chain is also observed in D₂O. Tilt angles for the octyl chain (1.0-10.8°) are consistent with an ordered monolayer at the air-liquid interface.

Original language	English
Pages (from-to)	16079-16085
Number of pages	7
Journal	Journal of Physical Chemistry C
Volume	122
Issue number	28
DOIs	https://doi.org/10.1021/acs.jpcc.8b03680
State	Published - Jul 19 2018
Externally published	Yes

Funding

This work is supported in part by a grant from the National Science Foundation (NSF; grant CBET-1705817). The authors also thank NSF (grants CHE-0947031 and CHE-1338000) for the acquisition of the femtosecond laser and nuclear magnetic spectrometer. K.K. and E.M. thank NSF (grant CHE-1507321), the American Chemical Society Petroleum Research Fund (grant 56375-ND4) and the Roenigk Foundation for their ongoing support. The authors would like to thank Drs. David Young, Srdjan Nesic, and Sumit Sharma from the Institute of Corrosion and Multiphase Technology (ICMT) in the Department of Chemical and Biomolecular Engineering at Ohio University for fruitful discussions. Additionally, the authors are grateful to multiple Ohio University entities for additional financial support (the Department of Chemistry and Biochemistry, the College of Arts and Sciences, the Vice President for Research, the Nanoscale and Quantum Phenomena Institute, and the Condensed Matter and Surface Science program).

Funders	Funder number
Department of Chemistry and Biochemistry
Nanoscale and Quantum Phenomena Institute
Roenigk Foundation
National Science Foundation	CHE-1507321, CBET-1705817
American Chemical Society Petroleum Research Fund	56375-ND4
Ohio University
College of Arts and Sciences, Boston University

Access to Document

10.1021/acs.jpcc.8b03680

Cite this

@article{b0f1a3bd7a4349dfb6a68ee647d378a6,

title = "Solvent Isotopic Effects on a Surfactant Headgroup at the Air-Liquid Interface",

abstract = "The geometry, arrangement, and orientation of a quaternary ammonium surfactant flanked by two methyl groups, a benzyl head, and an octyl tail were assessed at the air-water and air-deuterium oxide (D2O) interfaces using sum frequency generation vibrational spectroscopy. Remarkably, symmetric and asymmetric N-CH3 stretches (at ∼2979 and ∼3045 cm-1, respectively, in the SSP polarization combination) were visible in water but negligible in deuterium oxide. We concluded that D2O addition triggers the average reorientation of the dimethyl amino units parallel to the interface and possibly changes the overall conformation of the surfactant. A reduced number of gauche defects in the surfactant octyl chain is also observed in D2O. Tilt angles for the octyl chain (1.0-10.8°) are consistent with an ordered monolayer at the air-liquid interface.",

author = "Premadasa, {Uvinduni I.} and Negar Moradighadi and Kondalarao Kotturi and Jeeranan Nonkumwong and Khan, {Md Rubel} and Marc Singer and Eric Masson and Cimatu, {Katherine L.A.}",

note = "Publisher Copyright: {\textcopyright} 2018 American Chemical Society.",

year = "2018",

month = jul,

day = "19",

doi = "10.1021/acs.jpcc.8b03680",

language = "English",

volume = "122",

pages = "16079--16085",

journal = "Journal of Physical Chemistry C",

issn = "1932-7447",

publisher = "American Chemical Society",

number = "28",

}

TY - JOUR

T1 - Solvent Isotopic Effects on a Surfactant Headgroup at the Air-Liquid Interface

AU - Premadasa, Uvinduni I.

AU - Moradighadi, Negar

AU - Kotturi, Kondalarao

AU - Nonkumwong, Jeeranan

AU - Khan, Md Rubel

AU - Singer, Marc

AU - Masson, Eric

AU - Cimatu, Katherine L.A.

PY - 2018/7/19

Y1 - 2018/7/19

N2 - The geometry, arrangement, and orientation of a quaternary ammonium surfactant flanked by two methyl groups, a benzyl head, and an octyl tail were assessed at the air-water and air-deuterium oxide (D2O) interfaces using sum frequency generation vibrational spectroscopy. Remarkably, symmetric and asymmetric N-CH3 stretches (at ∼2979 and ∼3045 cm-1, respectively, in the SSP polarization combination) were visible in water but negligible in deuterium oxide. We concluded that D2O addition triggers the average reorientation of the dimethyl amino units parallel to the interface and possibly changes the overall conformation of the surfactant. A reduced number of gauche defects in the surfactant octyl chain is also observed in D2O. Tilt angles for the octyl chain (1.0-10.8°) are consistent with an ordered monolayer at the air-liquid interface.

AB - The geometry, arrangement, and orientation of a quaternary ammonium surfactant flanked by two methyl groups, a benzyl head, and an octyl tail were assessed at the air-water and air-deuterium oxide (D2O) interfaces using sum frequency generation vibrational spectroscopy. Remarkably, symmetric and asymmetric N-CH3 stretches (at ∼2979 and ∼3045 cm-1, respectively, in the SSP polarization combination) were visible in water but negligible in deuterium oxide. We concluded that D2O addition triggers the average reorientation of the dimethyl amino units parallel to the interface and possibly changes the overall conformation of the surfactant. A reduced number of gauche defects in the surfactant octyl chain is also observed in D2O. Tilt angles for the octyl chain (1.0-10.8°) are consistent with an ordered monolayer at the air-liquid interface.

UR - http://www.scopus.com/inward/record.url?scp=85049366172&partnerID=8YFLogxK

U2 - 10.1021/acs.jpcc.8b03680

DO - 10.1021/acs.jpcc.8b03680

M3 - Article

AN - SCOPUS:85049366172

SN - 1932-7447

VL - 122

SP - 16079

EP - 16085

JO - Journal of Physical Chemistry C

JF - Journal of Physical Chemistry C

IS - 28

ER -

Solvent Isotopic Effects on a Surfactant Headgroup at the Air-Liquid Interface

Abstract

Funding

Access to Document

Other files and links

Fingerprint

Cite this