Adsorption of krypton and nitric oxide on alkali metal chloride films

Abstract

The adsorption of krypton and nitric oxide on evaporated films of LiCl, NaCl, KCl and CsCl has been investigated between –160 and –197°C. Isosteric heats of adsorption at low coverage show reasonable agreement with values estimated by comparing previously calculated heats for argon on these adsorbents with equilibrium separation energies corresponding to a 9 : 6 intermolecular potential function. The interaction of nitric oxide with NaCl, KCl and CsCl is comparable to that of krypton and argon, but LiCl shows some evidence for an additional ion-quadrupole effect. Surface areas determined from krypton adsorption by the Kaganer method are generally two to three times lower than the B.E.T. values. The variation of isosteric heats with coverage is discussed.