Publications
Lucovsky, G.; Zhang, Y.; Fulton, C. C.; Zou, Y.; Nemanich,
R. J.; Ade, H.; Whitten, J. L. Final
state effects in VUV and soft X-ray absorption spectra of transition metal
oxides and silicate alloys: comparisons between experiment and ab initio calculations.
Journal of Electron Spectroscopy and Related Phenomena (2005), 144-147, 917-919.
Fulton, C. C.; Lucovsky, G.; Zhang, Y.; Zou, Y.; Nemanich,
R. J.; Ade, H.; Whitten, J. L. Studies of the coupling of final d*-states in mixed Hf and Ti
oxides (HfO2)x(TiOx)1-x and
other complex oxides. Journal of Electron Spectroscopy and Related Phenomena (2005), 144-147, 913-916.
C.-Y. Qin and J. L. Whitten, Adsorption of O, H, OH and
H2O on Ag(100), J. Phys. Chem. B (2005), 109(18), 8852-8856.
Kokh, Daria B.; Buenker, Robert J.; Liebermann, Heinz-Peter; Pichl, Lukas; Whitten, Jerry
L. Theoretical Study of the CH2 + O Photodissociation of Formaldehyde Adsorbed on the
Ag(111) Surface. Journal of Physical Chemistry B (2005), 109(38), 18070-18080.
M. Menon, R. J. Buenker and J. L. Whitten. Recombination of oxygen atoms on Ag(111)
doped with subsurface impurity atoms of different electronegativity,
manuscript, to be submitted for publication (2005).
Lucovsky, Gerald; Fulton, C. C.; Zhang, Y.; Zou, Y.; Luning,
J.; Edge, L. F.; Whitten, J. L.; Nemanich, R. J.;
Ade, H.; Schlom, D. G.; Afanase'v, V. V.; Stesmans, A.; Zollner,
S.; Triyoso, D.; Rogers, B. R. Conduction band-edge states associated
with the removal of d-state degeneracy by the Jahn-Teller
effect. IEEE Transactions on Device
and Materials Reliability (2005), 5(1), 65-83.
Daria B. Kokh, Robert J. Buenker, and Jerry L. Whitten.
Trends in adsorption of open-shell atoms and small
molecular fragments on the Ag(111) surface, Surface Science 600 (2006), 5104–5113
Qin, Changyong; Sremaniak, Laura S.; Whitten, Jerry L. CO adsorption on
Ag(100) and Ag/MgO(100). Journal of Physical Chemistry B (2006), 110(23), 11272-11276.
Laura S. Sremaniak, Jerry L. Whitten, Matthew J. Truitt, Jeffery L. White.
Weak Hydrogen Bonding Can Initiate Alkane C-H Bond Activation in Acidic Zeolites, J. Phys.
Chem. B (2006), 110, 20762-20764.
C.M. Osburn, S.A. Campbell, A. Demkov, E. Eisenbraun,
E. Garfunkel, T. Gustafsson, A.I. Kingon, J. Lee, D.J. Lichtenwalner,
G. Lucovsky, T.P. Ma, J.P. Maria, V. Misra, R.J. Nemanich, G.N.
Parsons, D.G. Schlom, S. Stemmer, R.M. Wallace, and
J. Whitten. Materials and Processes for
High k Gate Stacks: Results from the FEP Transition Center, ECS Transactions, 3(3), 389 (2006)
L. S. Sremaniak and J. L. Whitten. Theoretical treatment of excited electronic states of
adsorbates on metals: electron attachment to CO2 adsorbed
on Pt(111), Surface Science (in press) 2007
G. Lucovsky and J. L. Whitten.
Metal Gate Electrodes: Theoretical Studies of Zr/ZrO2 and Hf/HfO2
interfaces, Surface Science (in press) 2007.
Abstracts of Recent Work
Theoretical treatment of excited electronic states of adsorbates on metals:
electron attachment to CO2 adsorbed on Pt(111)
L. S. Sremaniak and J. L. Whitten, Surface Science (in press) 2007
Abstract.
Photochemistry involving adsorbates on metals often
proceeds by photoexcitation of the metal followed by
transient attachment of photo emitted electrons to the adsorbate.
First principles theoretical methods suitable for describing electronic states
embedded in a near continuum of metal to metal excitations are described and an
application to electron attachment to CO2 adsorbed on Pt(lll) is reported. Wavefunctions
are constructed by ab initio configuration
interaction methods which allow a rigorous resolution of states and
differentiation between competing pathways of molecular desorption
and dissociation. An embedding theory is used to achieve high accuracy in the
adsorbate-surface region. The overall process can be
understood as formation of an electron attached state at an
energy lower than the work function of the metal, localization of the
metal hole and attraction of the charged adsorbate to
the metal. Optimum geometries are calculated and pathways between these
geometries determine whether molecules will desorb,
dissociate by bond rupture directly in the excited electronic state, or
dissociate after return to the ground state potential energy surface via
vibrational processes. The influence of a
coadsorbed potassium electron donor atom on the energy
required to form the electron attachment state is also reported.
Weak Hydrogen Bonding Can Initiate Alkane C-H Bond Activation in Acidic
Zeolites
Laura S. Sremaniak, Jerry L. Whitten, Matthew J. Truitt, and Jeffery L. White.
J. Phys. Chem., Phys. Chem. B (2006), 110, 20762-20764.
Abstract. Ab initio calculations at the Hartree-Fock self-consistent
field/single determinant (SCF) and configuration interaction multi-determinant
(CI) expansion levels have been used to show that isobutane primary C-H bond
activation occurs via direct protium exchange with
the zeolite surface via a weakly hydrogen-bonded
complex. The calculated 15 kcal/mol activation barrier agrees with the 13.7
kcal/mol value from a recently reported experimental study (J. Am. Chem.
Soc. 2006, 128, 1847-1852).
Overall, the mechanism described in this contribution demonstrates that weak
C-H to O hydrogen bonding leads to complexes at the zeolite
acid site that can facilitate C-H bond activation.
Metal Gate Electrodes: Theoretical Studies of
Zr/ZrO2 and Hf/HfO2 Interfaces
G. Lucovsky and J. L. Whitten, Surface Science (in press) 2007.
Abstract. Ab initio quantum mechanical calculations have been
performed on cluster models of Zr/ZrO2 and Hf/HfO2
interfaces. The theoretical method is a first principles method in which
an exact electrostatic Hamiltonian is employed, except for core electron
effective potentials, and wavefunctions are constructed by a self-consistent-field
(SCF) method in which ionic correlation is included by local configuration
interaction (CI). The outcome of the calculations is a detailed prediction
of the electronic structure of the interface from which electrical properties
can be inferred; e.g., work function, surface dipoles, barriers to electron
transport, etc. The results are compared with and also serve
to calibrate electronegativity arguments that lead to predictions of surface dipole
changes when Zr or Hf metals are deposited on the respective elemental
oxides. In the present work the cluster describing the Zr/ZrO2 interface
was embedded in an electrostatic field that simulates more distant Madelung
contributions, and removes unphysical solutions as well.
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