Solvent choices

Solution phase UV-vis measurements use solutions of compounds which are dissolved in a solvent. The choice of solvent used for measurements requires consideration, particularly as many solvents will have absorbances in the UV-vis region. A solvent is only suitable to use for solution phase UV-vis spectroscopy if it has limited absorption across the wavelengths of interest, and this restricts many solvents to only being usable for particular wavelength ranges.

Alongside the solvent, it is important to consider the cuvette choices. Each cuvette type also has a usable working range of wavelengths, and many cuvettes also have restrictions for solvent compatibility (e.g. most polymer cuvettes are soluble in some solvents). More information on cuvettes can be found on the dedicated cuvette page.

The working ranges for many common solvents are summarised in the table below. These have been determined from the recorded UV-vis spectra for cuvettes and various solvents between 1000 and 200 nm, with these provided below the table. Thanks to Erica Overend for recording the spectra.

Usable wavelength ranges for solvents

Spectra

The spectra below have been recorded to show the absrbances from various solvents. The cuvette spectra have been recorded with the sample compartment holding the cuvette with an empty reference holder, recorded against a background with both compartments being empty. The solvents are recorded using matched quartz cuvettes, with an empty cuvette in the reference compartment and a solvent filled cuvette in the sample compartment, against a background of empty quartz cuvettes in the sample and reference compartments.

The data files for these spectra can be found in the sample data folders on the Teaching Labs Data Server.