Pd On Cu(1 1 1) Studied By Photoelectron Diffraction

The PdCu alloy system, which has important catalytic properties, has been the subject of many experimental and theoretical studies using a large number of different techniques. Theoretical and experimental structural studies converge in predicting ordered alloys for the Pd/Cu(1 1 0) and Pd/Cu(1 0 0) surfaces. No such agreement exists for the Pd/Cu(1 1 1) surface, however; indeed, few structural studies have been performed for this surface. Here, we report the first application of X-ray photoelectron diffraction (XPD) (using synchrotron radiation) in combination with LEED to determine the structure of ultra-thin epitaxial Pd films (∼1 ML) evaporated on Cu(1 1 1) single crystal surfaces. The analysis of the data was performed with the multiple scattering diffraction program of Chen and Van Hove. For the preparation condition used, a random surface alloy seems to form in the first three layers. The first interlayer distance expands whereas the second seems to contract. © 2002 Elsevier Science B.V. All rights reserved.504215222Tersoff, J., (1995) Phys. Rev. Lett., 74, p. 434. , and references thereinValden, M., Aaltonen, J., Pessa, M., Gleeson, M., Barnes, C.J., (1994) Chem. Phys. Lett., 228, p. 519Bardi, U., (1994) Rep. Prog. Phys., 57, p. 939Besenbacher, F., Chorkendorff, I., Clausen, B.S., Hammer, B., Molenbroek, A.M., Norskov, J.K., Stensgaard, I., (1998) Science, 279, p. 1913Choi, K.I., Vannice, M.A., (1991) J. Catal., 131, p. 36Anderson, J.A., Fernández-Garcia, M., Haller, G.L., (1996) J. Catal., 164, p. 477Illas, F., López, N., Ricart, J.M., Clotet, A., (1998) J. Phys. Chem. B, 102, p. 8017Barnes, C., Gleeson, M., (1994) Surf. Sci., 319, p. 157Murray, P.W., Stensgaard, I., Laegsgaard, E., Besenbacher, F., (1995) Phys. Rev. B, 52, p. 14404Murray, P.W., Stensgaard, I., Laegsgaard, E., Besenbacher, F., (1996) Surf. Sci., 365, p. 591Murray, P.W., Thorshaug, S., Stensgaard, I., Besenbacher, F., Laegsgaard, E., Ruban, A.V., Jacobsen, K.W., Skriver, H.L., (1997) Phys. Rev. B, 55, p. 1380Reilly, J.P., Barnes, C.J., Price, N.J., Bennett, R.A., Poulston, S., Stone, P., Bowker, M., (1999) J. Phys. Chem B, 103, p. 6521Wu, S.C., Lu, S.H., Wang, Z.Q., Lok, C.K.C., Quinn, J., Li, Y.S., Tian, D., Jona, F., (1988) Phys. Rev. B, 38, p. 5363Garces, J.E., Mosca, H.O., Bozzolo, G.H., (2000) Surf. Sci., 459, p. 365Garces, J.E., Bozzolo, G.H., Abel, P., Mosca, H.O., (2000) Appl. Surf. Sci., 167, p. 18Rousset, J.L., Bertolini, J.C., Miegge, P., (1996) Phys. Rev. B, 53, p. 4947Ruban, A.V., Skriver, H.L., Norskov, J.K., (1999) Phys. Rev. B, 59, p. 15990Barnes, C.J., Gleeson, M., Sahrakorpi, S., Lindroos, M., (2000) Surf. Sci., 447, p. 165Fujinaga, Y., (1979) Surf. Sci., 84, p. 1Aaen, A.B., Laegsgaard, E., Ruban, A.V., Stensgaard, I., (1998) Surf. Sci., 408, p. 43Lopez, N., Norskov, J.K., (2001) Surf. Sci., 477, p. 59Baddeley, Cj., Barnes, C.J., Wander, A., Ormerod, R.M., King, D.A., Lambert, R.M., (1994) Surf. Sci., 314, p. 1De Castro, A.R.B., Fraguas, G.B., Fonseca, P.T., Suave, R.N., Gama, S., Coelho, A.A., Santos, I.A., (1999) J. Electron. Spectrosc. Relat. Phenomen., 103, p. 725Chen, Y., Van Hove, M.A., http://electron.lbl.gov/mscdpack/Chen, Y., De Abajo, F.J.G., Chasse, A., Ynzunza, R.X., Kaduwela, A.P., Van Hove, M.A., Fadley, C.S., (1998) Phys. Rev. B, 58, p. 13121Soares, E.A., De Siervo, A., Landers, R., Kleiman, G.G., (2002) Surf. Sci., 497, p. 20