While the mixture of lidocaine and decanoic acid is a deep eutectic solvent (DES), the ternary mixture of these two compounds with water presents a complex phase diagram in which several regions can be exploited for liquid phase extraction. We here aim at characterizing the structural organization (micelle or cluster formation, correlation lengths, aggregation) over a large part of the phase diagram, including the DES, in order to understand the mechanisms leading to the phase separation. We propose to use a home-built cell for in-situ dilution and efficient phase diagram characterization. We request for this purpose 9 shifts on D2AM.