Direct inelastic scattering of N/sub 2/ from Ag(111). II. Orientation

Journal Article · Mon Aug 15 04:00:00 EDT 1988 · J. Chem. Phys.; (United States)

OSTI ID:7185650

Sitz, G O; Kummel, A C; Zare, R N; Tully, J C

The orientation of the angular momentum of N/sub 2/ scattered from clean Ag(111) is determined by resonance-enhanced multiphoton ionization. The orientation is the net helicity or handedness of the sense of rotation, i.e., clockwise vs counterclockwise. The orientation of the scattered N/sub 2/ is measured along a direction perpendicular to the scattering plane. The degree and sign of the orientation is found to depend strongly on the final rotational quantum number J and on the final scattering angle. The results require that there are forces acting in the plane of the surface during the scattering. The observed behavior can be reproduced qualitatively by a conventional hard-cube, hard-ellipsoid model to which a tangential friction has been introduced to account for the in-plane forces. This produces a splitting of the rotational rainbow peak which leads to changes of sign of the orientation as a function of rotational quantum number. Thus, orientation measurements provide a unique probe of in-plane gas--surface forces.

• Research Organization: Department of Chemistry, Stanford University, Stanford, California 94305
• OSTI ID: 7185650
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 89:4; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

656003* -- Condensed Matter Physics-- Interactions between Beams & Condensed Matter-- (1987-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALIGNMENT
ANGULAR MOMENTUM
BEAMS
COLLISIONS
ELEMENTS
ENERGY LEVELS
EXCITED STATES
IONIZATION
METALS
MOLECULAR BEAMS
MOLECULE COLLISIONS
MULTI-PHOTON PROCESSES
NITROGEN
NONMETALS
ORIENTATION
PHOTOIONIZATION
ROTATIONAL STATES
SILVER
SURFACES
TRANSITION ELEMENTS