Neutron and hard X-ray diffraction measurements on liquid methanol at room
temperature are presented at pressures ranging from 1 bar to 9 kbar. Under
ambient conditions a complete partial structure factor analysis has been pe
rformed. The partial structures are not all in agreement with simulation re
sults. Notably, the data show no sign of a sharp feature in the H-O(O/C) pa
rtial, implying that the hydrogen between the hydrogen bonded oxygen is les
s localized than predicted by the standard simulation potentials. The data
have been analysed using a continuous random network approach common in the
analysis of the structure of tetrahedral network glasses. The pressure-ind
uced change in the scattering intensity is restricted to the momentum trans
fer range (0 < Q < 2.5 Angstrom(-1)), i.e., there is no discernible change
in sharp real-space structures. Up to 9 kbar the change in scattering inten
sity scales to a good approximation with the density.