In the mono-alcohols (ROH) there is a competition between the packing requirements of the R-group and for the hydroxyl groups to be sufficiently close for hydrogen bonding to occur. The packing motifs can be chains, or catemers, if the R-group is sufficiently small. For bulkier R-groups the molecules may no longer form hydrogen bonded catemers but cyclic rings can be created. We have been studying a series of R-OH systems at pressure and we have recently found a previously unobserved structure of 2,2,2-trifluoro-ethanol (phase-II) where the R-groups are small enough to allow catemer formation. We have studied this high-pressure structure on PEARL (RB1820042) and discovered a second high-pressure structure (phase-III) at a slightly elevated pressure. We now seek time to to gain more detail of the phase-II to III transition and accurately pinpoint the onset of freezing at room temperature.