DTIC QT,, ALT. ns . ME MIlollfJ94 6 1 087form Approved REPORT DOCUMENTATION PAGE o1m 8 4:=,m--;~I 0 .1fft -C-tP-PU-W1KA.t AV0014t~a.9 -% stmated to 41wwqe 1 %,wig ow rosoon, maIudm9 thme 1~fo refvwtnq mIWWudmOAI. Warxew" ewtranIM data Wofte%P3a~' ape ftaptauewg we ta ne~gd. and (cfleti9 ago fft4*.flq trn. a-mttwn of SInoIUI*tSon so"4 crnaeunts e, ABSTRACT (Maximm 20words)We have used scanning tunneling microscopy to probe the molecular scale structures of pure and mixed composition self-assembled monolayers of CH 3 (CH 2 ) 15 SH and CH 3 0 2 C(CH 2 ) 15 SH on gold. A predominant defect structure is found for both films and is assigned as a void defect in the thiolate overlayer. The mixed composition films are observed to phase segregate into domains of the pure component thiolates. Tune-lapse series of scanning tunneling microscope images reveal kink-driven motion at step edges and exchange of thiolate molecules on terraces.14.

No abstract