IR sample preparation for pure liquid samples What

IR sample preparation for pure liquid samples

What is a thin film cell? a thin film cell n is a drop of pure liquid sample n sandwiched between salt (Na. Cl) discs n

Thin film IR cells Salt (Na. Cl) discs are used n To hold the sample n So the holder won’t absorb infrared light n and only sample absorption is detected n

Sample preparation so only dry (anhydrous) samples are used n because even traces of water etch the IR discs n affecting the path length of light n and the optical quality of discs n

use clean gloves to work with salt discs put on an extra pair of gloves n to protect cells n from anything aqueous on your regular gloves n

Preparing salt discs Slide off n The top of the n Desiccator n Remove n Salt discs n

replace n desiccator cover n immediately n remove discs n from sleeves and n rest on kim wipe n

to cleann discs add a few drops of chloroform n to each disc n rub gently n to clean off n all traces of sample n n …

adding sample n add one or two drops n n n n of sample in the middle of the 1 st disc lower the 2 nd disc on top as shown to spread sample evenly

placing discs in cell holder use your finger n to make a platform n in the cell holder n lower in n the Na. Cl discs n do not wedge them n

gently n place lid n on top n slide into position n in light beam n

close n sample n compartment n remove gloves n before using n keyboard n

to cleann discs add a few drops of chloroform n to each disc n rub gently n to clean off n all traces of sample n n …

Keep discs dry n n replace in desiccator after cleaning …