Understanding the Electronic Structure
Properties of Bare Silver Clusters
as Models for Plasmonic Excitation
Lindsey R. Madison, Mark A. Ratner and George C. Schatz
Abstract We present a detailed study of the optical properties of tetrahedral silver
clusters ranging from Ag 10 to Ag 220 using frequency domain (FD) and real-time
(RT) time-dependent density functional theory. We compare the electronic structure
and optical properties of the clusters calculated with different exchange-correlation
functionals, different basis sets, and different DFT software packages. We also
present an analysis of the orbital contributions to the density of states, which for the
larger clusters can be decomposed into surface and bulk contributions. We find that
the description of optical properties is nearly insensitive to the choice of exchangecorreleation functional and results are consistent for FD and RT implementations.
Optical properties are sensitive to basis set selection however, and it is critical that
the basis set correctly describes d-orbitals. We show that FD-TDDFT provides
insights into the collective excitation nature of a plasmonic nanoparticle allowing us
to investigate the hot electron distribution produced immediately after plasmonic
excitation. This analysis shows that the electron distribution is largely a flat function
of electron energy in the range between zero and the photon energy for a plasmonic
transition whereas it is strongly peaked close to zero for an interband transition.
Keywords Nanoparticle Á Optical Response Á Intraband Transition Á Time
Dependent Density Functional Theory Á Hot Electrons
L.R. Madison Á M.A. Ratner Á G.C. Schatz (&)
Department of Chemistry, Northwestern University,
Evanston, IL 60208-3113, USA
e-mail: schatz@northwestern.edu
L.R. Madison
e-mail: madisonl@u.northwestern.edu
M.A. Ratner
e-mail: ratner@northwestern.edu
© Springer International Publishing Switzerland 2015
M.A.C. Nascimento et al. (eds.), Frontiers in Quantum Methods and Applications
in Chemistry and Physics, Progress in Theoretical Chemistry and Physics 29,
DOI 10.1007/978-3-319-14397-2_3
37
Properties of Bare Silver Clusters
as Models for Plasmonic Excitation
Lindsey R. Madison, Mark A. Ratner and George C. Schatz
Abstract We present a detailed study of the optical properties of tetrahedral silver
clusters ranging from Ag 10 to Ag 220 using frequency domain (FD) and real-time
(RT) time-dependent density functional theory. We compare the electronic structure
and optical properties of the clusters calculated with different exchange-correlation
functionals, different basis sets, and different DFT software packages. We also
present an analysis of the orbital contributions to the density of states, which for the
larger clusters can be decomposed into surface and bulk contributions. We find that
the description of optical properties is nearly insensitive to the choice of exchangecorreleation functional and results are consistent for FD and RT implementations.
Optical properties are sensitive to basis set selection however, and it is critical that
the basis set correctly describes d-orbitals. We show that FD-TDDFT provides
insights into the collective excitation nature of a plasmonic nanoparticle allowing us
to investigate the hot electron distribution produced immediately after plasmonic
excitation. This analysis shows that the electron distribution is largely a flat function
of electron energy in the range between zero and the photon energy for a plasmonic
transition whereas it is strongly peaked close to zero for an interband transition.
Keywords Nanoparticle Á Optical Response Á Intraband Transition Á Time
Dependent Density Functional Theory Á Hot Electrons
L.R. Madison Á M.A. Ratner Á G.C. Schatz (&)
Department of Chemistry, Northwestern University,
Evanston, IL 60208-3113, USA
e-mail: schatz@northwestern.edu
L.R. Madison
e-mail: madisonl@u.northwestern.edu
M.A. Ratner
e-mail: ratner@northwestern.edu
© Springer International Publishing Switzerland 2015
M.A.C. Nascimento et al. (eds.), Frontiers in Quantum Methods and Applications
in Chemistry and Physics, Progress in Theoretical Chemistry and Physics 29,
DOI 10.1007/978-3-319-14397-2_3
37