MONOLAYER KR FILMS ADSORBED ON BN

We have conducted a detailed study of Kr films adsorbed on BN. We have performed adsorption-isotherm measurements and calculations for the p otential energy of Kr atoms on the surface of BN. Both the experimenta l and the theoretical results are extensively compared to data for Kr on graphite, as well as to data for N-2 and CO on both BN and graphite . For N-2 and CO, the energy calculations found similar corrugations o n BN and on graphite (these two molecular adsorbates do not discrimina te between the B and N atoms on the BN substrate). This is not the cas e for Kr. The corrugation for Kr atoms (which do discriminate between B and N) is quite different on BN from what it is on graphite. Our ads orption isotherms indicate that a commensurate solid phase is present for Kr on BN. However, this commensurate solid exists only over a surp risingly narrow temperature interval of less than 5 K. Our experimenta l results are compared with those from previous studies of this system . We offer possible explanations for the differences observed and atte mpt to present a coherent picture of the experimental situation for th is system.