@article{lemaire_measurement_2002, title = {The measurement by {SAXS} of the nematic order parameter of laponite gels}, volume = {59}, issn = {0295-5075}, abstract = {We performed small-angle X-ray scattering (SAXS) experiments on oriented samples of laponite clay gels obtained by slow evaporation. The SAXS patterns are clearly anisotropic, which demonstrates the existence of nematic-like orientational correlations of the laponite disc-like particles. The iso-intensity lines of the SAXS patterns are elliptical and roughly homothetic over the whole scattering vector range examined in this experiment. The value of the nematic order parameter, S = 0.55 +/- 0.05, derived from the SAXS patterns is comparable to that of usual liquid crystals. This large value proves the importance of orientational correlations in these gels at concentrations higher than 0.02 g . cm(-3), even in the absence of shear.}, number = {1}, journal = {Europhysics Letters}, author = {Lemaire, B.J. and Panine, P. and Gabriel, J.C.P. and Davidson, P.}, year = {2002}, pages = {55--61}, }