  The advent of liquid $\mu$-jet setups as proposed by Faubel and Winter in
conjunction with X-ray Photoemission Spectroscopy (XPS) has opened up a large
variety of experimental possibilities in the field of atomic and molecular
physics. In this study, we present first results from a synchrotron-based XPS
core level and valence band electron spectroscopy study on water (10$^{-4}$M
aqueous NaCl solution) as well as a water-methanol mixture using the newly
commissioned ALBA liquid $\mu$-jet setup. The experimental results are compared
with simulations from density functional theory (DFT) regarding the electronic
structure of single molecules, pure molecular clusters, and mixed clusters
configurations as well as previous experimental studies. We give a detailed
interpretation of the core level and valence band spectra for the vapour and
liquid phases of both sample systems. The resulting overall picture gives
insight into the water-methanol concentrations of the vapour and liquid phases
as well as into the local electronic structure of the pertinent molecular
clusters under consideration, with a special emphasis on methanol as the
simplest amphiphilic molecule capable of creating hydrogen bonds.
