Greg O. Sitz
Professor
Physics Department
University of Texas
Austin, Texas 78712
- Office: RLM 10.313 :: Lab: RLM 2.420
- Office Phone: (512) 471-0701
- Lab Phone: (512) 471-0788
- Fax: (512) 471-9637
- Email: gositz@physics.utexas.edu
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Greg O. Sitz
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 Apparatus |
H2 Scattering |
D2 Scattering |
N2 Scattering |
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This is the Ultra-High Vacuum (UHV) scattering chamber in which the state-resolved experiments are performed. The cylinder in the center of the appartus is the Main chamber which houses the LEED (Low Energy Electron Diffraction) and Auger spectroscopy, ion sputtering gun, quadrupole and time-of-flight (TOF) mass spectrometers and window ports for laser access. The surface is mounted on a manipulator and can be heated (electron bombardment) or cooled to liquid nitrogen temperature. The manipulator is mounted on the lid of the main chamber which can be rotated to place the surface in front of the ion gun for cleaning, or LEED for surface analysis, or in front of the molecular beam for scattering experiments. |
The chamber off to the right is the source chamber and it contains the nozzle and skimmer. In between the source and main chambers there is a small buffer chamber which houses the chopper (a small disk with slits that rotates around 300 Hz). The tall cylinder on the left of the picture is a liquid nitrogen trap. The molecular beam is created by a pulsed nozzle that works like a fuel injector in a car. Inside the nozzle is 2 or 3 atm of gas and when the aperture opens (solenoid driven) the gas rushes out into the vacuum in a supersonic expansion. The molecules in the beam will be very cold rotationally (about 6 K for Nitrogen) and have a narrow velocity distribution. This means that the molecules incident on the surface all have nearly the same velocity. By heating the nozzle or mixing the gas in Helium or Hydrogen we can change that velocity and study the dependence of the scattered distributions on incident energy. |
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Elizabeth Watts and GOS, State-to-state scattering in a reactive system: H2(v=1,J=1) from Cu(100), J. Chem. Phys. 114 (2001) pp 4171-4179. |
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E. Watts, GOS, D. A. McCormack, G. J. Kroes, R. A. Olsen, J. A. Groeneveld, J. N. P. van Stralen, E. J. Baerends, and R. C. Mowrey, Rovibrationally inelastic scattering of (v=1,J=1) H2 from Cu(100): Experiment and Theory, J. Chem. Phys. 114 (2001) pp 495-503. |
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Elizabeth Watts and GOS, Surface Temperature Dependence of Rotational Excitation of H2 Scattered from Pd(111), J. Chem. Phys. 111 (1999) pp 9791-9796. |
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Michael Gostein and GOS, Rotational state-resolved sticking coefficients for H2 on Pd(111): Testing dynamical steering in dissociative adsorption, JCP 106 (1997) pp 7378-7390. |
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Michael Gostein and GOS, Scattering of H2 (v=1,J=1) from Cu(110): Survival probability versus incident energy, JVST A 14 (1996) pp 1562-1565. |
Back to the top| Leah C. Shackman and GOS "Scattering of D2 from Cu(100) and Pd(111)", J. Chem. Phys. 123, 064712 (2005) |
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Leah C. Shackman and GOS "Rotationally Inelastic Scattering of HD from Cu(100) and Pd(111)", 122 (2005) pp 114702-1-5. |
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Time-of-flight data for Raman pumped D2(v=1,J=2) scattering from Cu(100) showing both elastic and inelastic scattering.  |
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Jennifer L. W. Siders, and GOS, Multibounce direct scattering of N2 from Cu(110): Experiment and trajectory simulations, JVST A 13 (1995) pp 1400-1404. | ||
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Jennifer L. W. Siders, and GOS, Observation and characterization of direct inelastic and trapping-desorption channels in the scattering of N2 from Cu(110), JCP 101 (1995) pp 6264-6270. | ||
| David Schlichte, Masters Thesis, University of Texas,December 2000 | ||
| Jonathan Prejean, Masters Thesis, University of Texas, December 1998 | ||
| Michelle Gotthold, Masters Thesis, University of Texas, August 1998 |
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