The densimeter is a DMA 4500 M (Anton Paar) that uses the oscillating U-tube principle (accuracy and repeatability 5 • 10 -5 and 5 • 10 -6 g/cm 3 , respectively). The viscometer is a Lovis 2000 ME (Anton Paar) falling ball micro-viscometer with 0.5% accuracy and 0.1% repeatability. The capillary diameter was 1.59 mm and a gold coated ball (1.5 mm diameter) was used to prevent corrosion. The two systems, coupled in series in the same equipment, include ThermoBalance ™ temperature management, which allows to quickly perform accurate measurements at different temperatures, guaranteeing long-term stability for temperature scans. Upon injecting the sample, the liquid fills both the densimeter and the viscometer simultaneously. Approximately 2 mL is needed to fill the system. The samples were 4 mL, injected via a 6 mL syringe. Between each measurement, the cavities were purged injecting solvents in the following order: water-dryingacetone-drying. Deionized water was used to dilute and evacuate vanadium compounds whilst acetone was used to evacuate water for fast drying. We performed repeatability measurements to ensure that this cleaning protocol matched the values given by the manufacturer. Additionally, we regularly checked the densimeter and viscometer calibrations, ensuring that there was no remaining residue inside the system.