On the dominance of an indirect mechanism for photon stimulated ion desorption from SrTiO3(100)-H2O

A679 Surface Science 178 (1986) 897-906 North-Holland, Amsterdam

897

OF AN INDIRECT MECHANISM ION DESORI’TION FROM SrTiO,(lOO)-H ,O

ON

THE

DOMINANCE

FOR PHOTON STIMULATED

I.W. OWEN *, N.B. BROOKES, D.R. WARBURTON Chemist?

Department,

F.M. QUINN,

Manchester

C.H. RICHARDSON

Unroersity, Manchester

**,

MI3 9PL, UK

D. NORMAN

Scrence and Engineering

Research Council, Dareshun,

Luboraton,

Warrington

WA4 4AD. UK

and G. THORNTON

***

Chemistq Department, Manchester University, Manchester and Science and Engineering Research Councrl, Daresbury Received

18 March

1986; accepted

for publication

Ml3 9PL, UK Laboratory, Warrington

WA4 4A D, UK

6 June 1986

The adsorption of H,O on fractured SrTi03(100) has been studied using photoemission and photon stimulated ion desorption (PSID). The photoemission results are, by comparison with data obtained on an Ar’ bombarded/annealed surface, consistent with dissociative H20 adsorption. PSID spectra recorded above the SrL, and TiK edges indicate that the dominant mechanism for ion desorption is X-ray induced electron stimulated desorption.

Surface Science 178 (1986) 907-916 North-Holland, Amsterdam

907

GROWTH AND ELECTRONIC AND Ag FILMS ON Al(111) B. FRICK and K. JACOBI

STRUCTURE

Fritz- Haher-Institut

der Max-Planck-Gesellsca~t,

Received

1986; accepted

17 March

for publication

Faradqweg

OF ULTRA-THIN

Pd

4 - 6. D-I 000 Berlin 33, German,,

18 June 1986

Pd and Ag films vapor-deposited onto Al(lll) were studied by AES, LEED and angle-resolved UPS. Both metals grow in the Stranski-Krastanov mode. With the substrate at 520 K Ag grows epitaliially. For Pd no ordered structures were found in the monolayer region. For Ag mainly two bands were found for the 4d states showing a maximum dispersion of 0.4 eV and a splitting into three bands in the outer parts of the two-dimensional Brillouin zone. In the monolayer the Pd4d emission lies 4 eV below the Fermi edge, which means that it maintains its atomic 4d’“5s0 configuration.