Dr. Allen L. Johnson
Assistant Professor
Physical Chemistry
Phone: (702) 895-0881
Fax: (702) 895-4072
E-Mail: aljohnson@ccmail.nevada.edu
Education:
Ph.D., University of California, Berkeley and Lawrence Berkeley Laboratory
(UCB/LBL), 1986:
Thesis title: "Platinum Surface Chemistry Studied by Thermal Desorption
Spectrometry and Near Edge X-ray Absorption Fine Structure: Absorbate Effects"
M.S., University of Washington (UW), 1979: Theoretical and Synthetic
Organic Chemistry
B.S., California Institute of Technology (CIT), 1977: Chemistry
Reed College, 1973-74
Major Teaching Responsibilities:
Quantum Chemistry (CHE 482)
Preparatory Chemistry (CHE 103)
Research Interests:
Dr. A. L. Johnson’s research is directed to the understanding of the structure
and dynamics of organic layers on surfaces. Recent advances in analytical
technique now allow the determination of detailed structural information
(orientation, bonding, and movements) of single molecule-thick layers on
surfaces, opening the door to a cross disciplinary approach to the design
of materials. The initial target studies are of Self-Assembled Monolayers
(SAMs) and Langmuir-Blodgett (LB) films. SAMs are typically hydrocarbon
thiols on gold, where the hydrocarbon chains form crystalline lattices
oriented perpendicularly to the surface. By the use of custom synthesized
hydrocarbon chains and the analytical techniques of Near Edge X-ray Absorption
Fine Structure (NEXAFS) and mass resolved-Electron Stimulated Desorption
Ion Angular Distributions (mr-ESDIAD) the design of surfaces with unique
properties (such as unique redox potentials and molecular recognition potential)
will be investigated. Dr. A. L. Johnson’s research also, typical of these
kinds of studies, has a methods development component. Solutions are being
sought for the charge neutralization problem for small spot XPS investigations
of insulators (for chemical speciation on the micron length scale) and
for the problems associated with the collection and analysis of photoelectron
holograms. Hydrocarbon thiols on gold, where the hydrocarbon chains form
crystalline lattices oriented perpendicularly to the surface. By the use
of custom synthesized hydrocarbon chains and the analytical techniques
of Near Edge X-ray Absorption Fine Structure (NEXAFS) and mass resolved-Electron
Stimulated Desorption Ion Angular Distributions (mr-ESDIAD) the design
of surfaces with unique properties (such as unique redox potentials and
molecular recognition potential) will be investigated.
Selected Publications:
R. D. Smith and A. L. Johnson, "Deposition Method for Moving Ribbon Liquid
Chromatography - Mass Spectrometer Interfaces," Anal. Chem. 53, 739 (1981).
A. L. Johnson, E. L. Muetterties, and J. Stöhr, "Orientation of
Complex Molecules Chemisorbed on Metal Surfaces: Near Edge X-Ray
Absorption Studies," J. Am. Chem. Soc. 105, 7183 (1983).
J. Stöhr, J. L. Gland, E. B. Kollin, R. Koestner, A. L. Johnson,
E. L. Muetterties, and F. Sette, "Desulfurization and Structural
Transformation of Thiophene on the Pt(111) Surface," Phys. Rev. Lett. 53,
2161 (1984).
A. L. Johnson, E. L. Muetterties, F. Sette, and J. Stöhr,
"Chemisorption Geometry of Pyridine on Pt(111) by NEXAFS," J. Phys. Chem.
89, 4071 (1985).
A. L. Johnson, M. M. Walczak, and T. E. Madey, "First Row Protic Hydrides
Adsorbed on Si(100), Structure and Reactivity," Langmuir, 4, 277 (1988).
A. L. Johnson, S. A. Joyce, and T. E. Madey, "Electron Stimulated Desorption
Ion Angular Distributions of Negative Ions," Phys. Rev. Lett., 61, 2578
(1988).
S. A. Joyce, A. L. Johnson, and T. E. Madey, "Methodology of Electron-Stimulated-Desorption
Ion-Angular Distributions (ESDIAD) of Negative Ions," J. Vac. Sci. Technol.
A7, 2221 (1989).
A. P. Hitchcock, M. J. McGlinchey, A. L. Johnson, W. K. Walter, M. Perez
Jigato, D. A. King, D. Norman, E. Rühl, C. Heinzel, and H. Baumgärtel,
"Inner-shell Spectroscopies of Solid and Gaseous Alkylidyne Tricobalt Nonacarbonyl
Complexes," J. Chem. Soc. Fara. Trans. 89, 3331 (1993).
A. Krasnopoler, A.L. Johnson and E. M. Stuve, "Hydrogen Bonding and
Molecular Orientation in Water/Fluorine Adlayers on Silver(110),"
Surf. Sci. 328, 186 (1995).
M. A. Golub, T. Wydeven, and A. L. Johnson, "On the Similarities of
Plasma-polymerized Tetrafluoroethylene and RF Plasma-sputtered Polytetrafluoroethylene",
Polymer Preprints 38(2), 668 (1997), Langmuir (in press).
A. L. Johnson, G. D. Ackermann, M. R. Howells, Z. Hussain, H. A. Padmore,
T. R. Renner, W. Steele, F. Gozzo, B. Triplett, R. Ynzunza, P. D. Kinney,
and R. Odom "Imaging on mXPS, Beamline 7.3.1.2: Resolution and Contrast"
ALS Compendium 1997 (in press).
Last updated 03-04-2000.
