Anomalous small-angle X-ray scattering from charged soft matter

Sztucki, Michael; Cola, Emanuela Di; Narayanan, Theyencheri

doi:10.1140/epjst/e2012-01627-x

Cited by 37 publications

(35 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This effect is expected in the case of an anomalous effect upon varying energy through the edge, and it demonstrates that Rb + ions decorate the micellar outer surface. Nevertheless, variation in I(q,E) is very mild; at 100 mM RbCl (Figure 5c), a concentration in counterions at which the anomalous effect was reported to be very important for polyelectrolytes and ionic surfactants systems, 62 (q) and v 2 (q) components, respectively, the nonresonant intensity of the macro-ion and the pure resonant contribution of the counterion, shown in Figure 5b,d. The splitting shows no noticeable effect on the 10 mM system using both the matrix and fit methods, as well as a mild anomalous effect on the 100 mM system, but only employing the matrix method.…”

Section: The Journal Of Physical Chemistry Bmentioning

confidence: 98%

Structure of Bolaamphiphile Sophorolipid Micelles Characterized with SAXS, SANS, and MD Simulations

et al. 2015

View full text Add to dashboard Cite

The micellar structure of sophorolipids, a glycolipid bolaamphiphile, is analyzed using a combination of small-angle X-ray scattering (SAXS), small-angle neutron scattering (SANS), and molecular dynamics (MD) simulations. Numerical modeling of SAXS curves shows that micellar morphology in the noncharged system (pH< 5) is made of prolate ellipsoids of revolution with core-shell morphology. Opposed to most surfactant systems, the hydrophilic shell has a nonhomogeneous distribution of matter: the shell thickness in the axial direction of the ellipsoid is found to be practically zero, while it measures about 12 Å at its cross-section, thus forming a "coffee bean"-like shape. The use of a contrast-matching SANS experiment shows that the hydrophobic component of sophorolipids is actually distributed in a narrow spheroidal region in the micellar core. These data seem to indicate a complex distribution of sophorolipids within the micelle, divided into at least three domains: a pure hydrophobic core, a hydrophilic shell, and a region of less defined composition in the axial direction of the ellipsoid. To account for these results, we make the hypothesis that sophorolipid molecules acquire various configurations within the micelle including bent and linear, crossing the micellar core. These results are confirmed by MD simulations which do show the presence of multiple sophorolipid configurations when passing from spherical to ellipsoidal aggregates. Finally, we also used Rb(+) and Sr(2+) counterions in combination with anomalous SAXS experiments to probe the distribution of the COO(-) group of sophorolipids upon small pH increase (5 < pH < 7), where repulsive intermicellar interactions become important. The poor ASAXS signal shows that the COO(-) groups are rather diffused in the broad hydrophilic shell rather than at the outer micellar/water interface.

show abstract

Section: The Journal Of Physical Chemistry Bmentioning

confidence: 98%

Structure of Bolaamphiphile Sophorolipid Micelles Characterized with SAXS, SANS, and MD Simulations

et al. 2015

View full text Add to dashboard Cite

show abstract

“…[68] . 与此同时, 通过PDDF [64] 形成是同步进行的 [68,91] . 按照这一方案, 可以通过在反离子元素吸收边附近改变X射线电子能量, 来分离出散射曲线中反离子的贡献 [26] .…”

Section: 由于反常小角X射线散射(asaxs)能够分离出saxsunclassified

The application of scattering technology in the study of polyoxometalate solutions

Zhao¹,

Lai²,

Zhang³

et al. 2018

Chin. Sci. Bull.

View full text Add to dashboard Cite

“…RSoXS and GI-RSoXS offers potential solutions to this challenge by using "soft" (i.e., low-energy) X-rays, which significantly reduce film damage and increase the contrast between organic domains; however, neither RSoXS nor GI-RSoXS has been employed widely for in situ experiments [223]. Additionally, anomalous small-angle X-ray scattering (ASAXS) is an emerging technique that exploits tunable X-ray energies to increase contrast between domains and could prove beneficial for analyzing side chain effects and templated metal deposition [93,121,224,225]. In particular, studies that incorporate these "soft" or resonant X-rays in reflectivity or grazing-incidence geometries will prove beneficial for further exploration of BCP thin films.…”

Section: Improving Resolution Reducing Data Collection Time-scales mentioning

confidence: 99%

Block copolymer thin films: Characterizing nanostructure evolution with in situ X-ray and neutron scattering

Shelton

Epps

2016

Polymer

View full text Add to dashboard Cite

Block copolymer (BCP) thin films have attracted significant attention as lithographic templates, separation membranes, and organic photovoltaic active layers for emerging nanotechnologies due to their ability to self-assembly into nanoscale features. To direct the selfassembly of BCP thin film nanostructures into ordered arrays, a suite of annealing techniques have been developed (e.g. thermal annealing, solvent vapor annealing, magnetic/electrical field alignment), each with its own set of controllable parameters and mechanisms for nanostructure reorganization. In this Review, we discuss the importance of in situ X-ray and neutron scattering for the study of BCP thin films subjected to different annealing protocols. These scattering approaches have become vital for understanding the complex nanostructure reorganization processes inherent in thin film fabrication and for establishing more consistent control over the morphology, ordering, and orientation. A major advantage of in situ X-ray and neutron scattering characterization is the ability to link the thermodynamic and kinetic pathways of nanostructure evolution over macroscopic (several cm 2) areas during annealing or processing. This feature has made in situ X-ray and neutron scattering ideal for refining annealing techniques, fostering robust assembly protocols, and developing the next-generation of directed assemblies. As the toolbox of viable processing methods continues to grow, we highlight potential opportunities to enhance current X-ray and neutron scattering capabilities through the improvement of scattering facilities, techniques, sample chambers, scattering/annealing protocols, and model development to establish universal control over BCP thin film selfassembly.

show abstract

Anomalous small-angle X-ray scattering from charged soft matter

Cited by 37 publications

References 51 publications

Structure of Bolaamphiphile Sophorolipid Micelles Characterized with SAXS, SANS, and MD Simulations

Structure of Bolaamphiphile Sophorolipid Micelles Characterized with SAXS, SANS, and MD Simulations

The application of scattering technology in the study of polyoxometalate solutions

Block copolymer thin films: Characterizing nanostructure evolution with in situ X-ray and neutron scattering

Contact Info

Product

Resources

About