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a b s t r a c tThe mechanism of how the neutral block in polyelectrolyte (PE) affects the interaction between PE and surfactants is investigated through coarse-grained simulations. We show that the neutral block plays profound roles on the structural formation of the PE/surfactant complex by assessing the adsorption of surfactants on a diblock or triblock PE and the resultant structures. For the diblock PE/surfactant system, adding a hydrophilic neutral block exerts little effect on the structural formation of the complex, while the presence of a hydrophobic neutral block enhances the adsorption of surfactants and facilitates the formation of a tri-layer core-shell structure. In the triblock PE/surfactant systems, two charged blocks located symmetrically at both ends of PE display asymmetric adsorption abilities for the surfactants. In addition, the presence of a charged middle block drives the PE/surfactant complex to form a micelle with two tails due to the hydrophilic blocks at both ends, while the hydrophobic ones drive the formation of a tri-layer core-shell structure with the PE chain showing a looped structure. If one end is hydrophilic and the other is hydrophobic, the complex tends to form a 'tadpole'-like structure in which the head is the tri-layered core-shell sphere, and the tail is the hydrophilic block.

We have found two distinctive structural modulations altering evidently along with the martensitic transition (MT) in the Ni 2 FeGa alloy. The first one ðq 1 Þ; corresponding to the well-known phonon anomalies in the ½zz0 TA 2 branch, occurs along the k110l direction. The second one ðq 2 Þ; an incommensurate modulation observed for the first time, occurs along the k211l-direction. Both modulations change gradually with the premartensitic phonon softening and discontinuously with the MT. Anomalies in magnetic properties emerging around the MT have been briefly discussed. q

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