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Odd-even Effect in Self-Assembly Patterns on Surface

12_bromo_fig3.jpg

Above (a) Structure of 12-bromododecanoic acid molecule in the all-trans conformation. Four molecules have been arranged to show the "up-and-down" profile described in the text. (b) Structure of 11-bromoundecanoic acid molecule in the all-trans conformation. Four molecules have been arranged to show the staircase-like profile described in the text.

For more detail, see: Fang, H.; Giancarlo, L.C.; Flynn, G.W.; J. Phys. Chem. B 1998, 102, 7421-7424.


Even Acid
odd_2.jpg

Above (a) STM image of 12-bromododecanoic acid (Br(CH2)11COOH) in phenyloctane on graphite. One molecular length is indicated by a black bar. Numbers 1-11 refer to the positions of 11 hydrogen on the 11 methylene carbons of a single molecule, and Br refers to the position of the Br atom. The image size is 12 X 12 nm2, and the imaging parameters are 1.4 V (sample negative) and 300 pA. (b) Top view of a computer-generated model of a 12-bromododecanoic acid film on a graphite substrate. Yellow represents bromine atoms, green represents carbon atoms, gray represents hydrogen atoms, and red represents oxygen atoms. The black lines outline the alternate "up-and-down" profile formed when the twin structures are assumed by 12-bromododecanoic acid on graphite.

For more detail, see: Fang, H.; Giancarlo, L.C.; Flynn, G.W.; J. Phys. Chem. B 1998, 102, 7421-7424.

Odd Acid
odd_3.jpg

Above (a) STM image of 11-bromoundecanoic acid (Br(CH2)10COOH) in phenyloctane on graphite. One molecule length is indicated by a black bar. The image size is 12 X 12 nm2, and the imaging parameters are 1.4 V (sample negative) and 300 pA. (b) Top view of a computer-generated model of an 11-bromoundecanoic acid film on a graphite substrate. The black lines outline the staircase-like profile formed when twin structures are assumed by 11-bromoundecanoic acid on graphite.

For more detail, see: Fang, H.; Giancarlo, L.C.; Flynn, G.W.; J. Phys. Chem. B 1998, 102, 7421-7424.