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The solvent effect occurs when the sample solvent is vaporized during injection and condenses on a cool column. Where "cool" is relative to the boiling point of the injection solvent and is often ten to twenty degrees below the boiling point of said solvent. Typically, this serves to trap analytes in a narrow band producing sharp peaks. However, solvent effects can also have a negative impact. In this example we have two main solvents as listed in the following table:

Solvent	Boiling Point
Acetone	56.5°C
Acetonitrile	82°C

The GC method in use, is one using splitless injection with an injector temperature of 250°C and an initial oven temperature of 70°C. Based on the boiling points we can see that there will be solvent effects from both acetone and acetonitrile. In the following chromatograms the concentration of acetone is increased while the concentration of acetonitrile is decreased and the concentration of the analytes is held constant. In effect this creates multiple solvent effects at the head of the column, resulting in the greatest peak distortion when the ratios are around 50:50. We can see that increasing acetone concentration decreases the amount of peak distortion until sharp peaks are obtained at a concentration of 90% acetone.