The effect of metal-molecule coupling on electron transport is examined in the prototypical case of alkane chains sandwiched between gold contacts and bridged by either amine or thiol groups. The results show that end group functionalization plays a crucial role in controlling electron transport, and that the symmetries and spatial extent of orbitals near the Fermi level control the conductivity rather than the strength of the bonding. For amine/Au and thiol/Au junctions, a crossover in conductivity with increasing bias is predicted.
REFERENCES
1.
Y.
Selzer
, A.
Salomon
, and D. J.
Cahen
, J. Phys. Chem. B
106
, 10432
(2002
).2.
A.
Nitzan
and M. A.
Ratner
, Science
300
, 1384
(2003
).3.
X. D.
Cui
, X.
Zarate
, J.
Tomfohr
, O. F.
Sankey
, A.
Primak
, A. L.
Moore
, T. A.
Moore
, D.
Gust
, G.
Harris
, and S. M.
Lindsay
, Nanotechnology
13
, 5
(2002
).4.
C.
Joachim
, J. K.
Gimzewski
, R. R.
Schlittler
, and C.
Chavy
, Phys. Rev. Lett.
74
, 2102
(1995
).5.
C.
Kergueris
, J. P.
Bourgoin
, S.
Palacin
, D.
Esteve
, C.
Urbina
, M.
Magoga
, and C.
Joachim
, Phys. Rev. B
59
, 12505
(1999
).6.
I.
Amlani
, A. M.
Rawlett
, L. A.
Nagahara
, and R. K.
Tsui
, Appl. Phys. Lett.
80
, 2761
(2002
).7.
C.
Chu
, J.-S.
Na
, and G. N.
Parsons
, J. Am. Chem. Soc.
129
, 2287
(2007
).8.
J. P.
Perdew
, K.
Burke
, and M.
Ernzerhof
, Phys. Rev. Lett.
77
, 3865
(1996
).9.
T.
Ozaki
, Phys. Rev. B
67
, 155108
(2003
).10.
T.
Ozaki
and H.
Kino
, Phys. Rev. B
69
, 195113
(2004
).11.
The density functional theory code, OpenMX, the basis orbitals, and the pseudopotentials used in this study are available on the web site http://www.openmx-square.org under the conditions of the GNU General Public License.
12.
N.
Troullier
and J. L.
Martins
, Phys. Rev. B
43
, 1993
(1991
).13.
S. G.
Louie
, S.
Froyen
, and M. L.
Cohen
, Phys. Rev. B
26
, 1738
(1982
).14.
P. E.
Blochl
, Phys. Rev. B
41
, 5414
(1990
).15.
B.
Larade
, J.
Taylor
, H.
Mehrez
, and H.
Guo
, Phys. Rev. B
64
, 075420
(2001
).16.
M.
Brandbyge
, J.-L.
Mozos
, P.
Ordejón
, J.
Taylor
, K.
Stokbro
, Phys. Rev. B
65
, 165401
(2002
).17.
M.
Buongiorno Nardelli
, J.-L.
Fattebert
, and J.
Bernholc
, Phys. Rev. B
64
, 245423
(2001
).18.
W.
Lu
, V.
Meunier
, and J.
Bernholc
, Phys. Rev. Lett.
95
, 206805
(2005
).19.
D.
Vanderbilt
, Phys. Rev. B
41
, 7892
(1990
).20.
J.-L.
Fattebert
and J.
Bernholc
, Phys. Rev. B
62
, 1713
(2000
).21.
S.
Datta
, Electronic Transport in Mesoscopic Systems
(Cambridge University Press
, Cambridge
, 1995
).22.
R.
Landauer
, Philos. Mag.
21
, 863
(1970
).23.
M.
Büttiker
, Phys. Rev. Lett.
57
, 1761
(1986
).24.
L.
Venkataraman
, J. E.
Klare
, I. W.
Tam
, C.
Nuckolls
, M. S.
Hybertsen
, and M. L.
Steigerwald
, Nano Lett.
6
, 458
(2006
).25.
A.
Bilić
, J. R.
Reimers
, N. S.
Hush
, and J.
Hafner
, J. Chem. Phys.
116
, 8981
(2002
).26.
F. T.
Arce
, M. E.
Vela
, R. C.
Salvarenzza
, and A. J.
Aevia
, Langmuir
14
, 7203
(1998
).27.
Y.
Yourdshahyan
, H. K.
Zhang
, and A. M.
Rappe
, Phys. Rev. B
63
, 081405
(2001
).28.
H.
Gronbeck
, A.
Curioni
, and W.
Andreoni
, J. Am. Chem. Soc.
122
, 3839
(2000
).29.
S.
Wang
, W.
Lu
, Q.
Zhao
, and J.
Bernholc
, Phys. Rev. B
74
, 195430
(2006
).30.
C.
Majumder
, H.
Mizuseki
, and Y.
Kawazoe
, J. Chem. Phys.
118
, 9809
(2003
).31.
Y.
Yourdshahyan
and A. M.
Rappe
, J. Chem. Phys.
117
, 825
(2002
).32.
S.
LaShell
, B. A.
McDougall
, and E.
Jensen
, Phys. Rev. Lett.
77
, 3419
(1996
).33.
W.
Tian
, S.
Datta
, S.
Hong
, R.
Reifenberger
, J. T.
Henderson
, and C. P.
Kubiak
, J. Chem. Phys.
109
, 2874
(1998
).© 2008 American Institute of Physics.
2008
American Institute of Physics
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