TY - JOUR
T1 - Scanning tunneling microscopy study of single molecule motion on the Si(100)- 2×1 surface
AU - Basu, R.
AU - Tovar, J. D.
AU - Hersam, M. C.
N1 - Funding Information:
The authors have benefited from discussions with Mark Ratner, Jeroen De Jonge, Will Gathright, Mark Greene, and Nathan Guisinger. This work was supported by the NASA Institute for Nanoelectronics and Computing (Award No. NCC 2-1363), the Nanoscale Science and Engineering Initiative of the National Science Foundation (Award Nos. EEC-0118025 and DMR-0134706), and the Defense University Research Initiative in Nanotechnology of the United States Army Research Office (Award No. DAAD 19-01-1-0521). One of the authors (J.D.T.) acknowledges an Early Career Development Award that is funded by the Baxter Healthcare Corporation and the Institute for BioNanotechnology in Advanced Medicine.
PY - 2005
Y1 - 2005
N2 - Room temperature ultrahigh vacuum (UHV) scanning tunneling microscopy (STM) is used to characterize the motion of individual organic molecules on the Si(100)- 2×1 surface. In particular, 4-methoxystyrene molecules are observed to translate laterally on the surface during UHV STM imaging. Switching between the two most favored conformations occurs on the time scale of 0.1-1 s. On the other hand, styrene molecules imaged under identical conditions are not observed to undergo lateral translations, thus suggesting that the rotational freedom of the methoxy group is enabling the apparent motion of 4-methoxystyrene. To test this hypothesis, the rotational freedom of the methoxy group was eliminated by synthesizing an analog molecule (5-vinyl-2,3-dihydrobenzofuran) where the methoxy group was covalently linked back to the aromatic ring. UHV STM studies of 5-vinyl-2,3-dihydrobenzofuran confirm the expected suppression of molecular motion. Overall, this study suggests that the motion of surface-mounted adsorbates can be controlled by engineering intramolecular rotational degrees of freedom.
AB - Room temperature ultrahigh vacuum (UHV) scanning tunneling microscopy (STM) is used to characterize the motion of individual organic molecules on the Si(100)- 2×1 surface. In particular, 4-methoxystyrene molecules are observed to translate laterally on the surface during UHV STM imaging. Switching between the two most favored conformations occurs on the time scale of 0.1-1 s. On the other hand, styrene molecules imaged under identical conditions are not observed to undergo lateral translations, thus suggesting that the rotational freedom of the methoxy group is enabling the apparent motion of 4-methoxystyrene. To test this hypothesis, the rotational freedom of the methoxy group was eliminated by synthesizing an analog molecule (5-vinyl-2,3-dihydrobenzofuran) where the methoxy group was covalently linked back to the aromatic ring. UHV STM studies of 5-vinyl-2,3-dihydrobenzofuran confirm the expected suppression of molecular motion. Overall, this study suggests that the motion of surface-mounted adsorbates can be controlled by engineering intramolecular rotational degrees of freedom.
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U2 - 10.1116/1.1949213
DO - 10.1116/1.1949213
M3 - Article
AN - SCOPUS:31144449524
SN - 1071-1023
VL - 23
SP - 1785
EP - 1789
JO - Journal of Vacuum Science and Technology B: Microelectronics and Nanometer Structures
JF - Journal of Vacuum Science and Technology B: Microelectronics and Nanometer Structures
IS - 4
ER -