Siegbahn

Ross B O and Siegbahn P E M 1977 The direet eonfiguration interaetion method from moleeular integrals Modern Theoretical Chemistry vo 3, ed H F III Sehaefer (New York Plenum) pp 277-318 give exeellent overviews of the Cl method For a niee overview of reeent work, see ... 

Roos B O, Taylor P R and Siegbahn P E M 1980 A complete active space SCF method (CASSCF) using a density matrix formulated super-CI approach Chem. Phys. 48 157-73... 

Neuhauser D, Baer M, Judson R S and Kouri D J 1989 Time-dependent three-dimensional body frame quantal wavepacket treatment of the atomic hydrogen + molecular hydrogen exchange reaction on the Liu-Siegbahn-Truhlar-Horowitz (LSTH) surfaced. Chem. Phys. 90 5882... 

Truhlar D G and Horowitz C J 1978 Functional representation of Liu and Siegbahn s accurate ab initio potential energy calculations for H + H2 J. Chem. Phys. 68 2466... 

K. Andersson, M, Blomberg, M, Fiilscher, G. Karlstrom, R. Lindh, P.-A, Malmqvist, P. Neogrady, J. Olsen, B, Roos, A, Sadlej, M. Schiitz, L. Seijo, L. Serrano-Andres, P. Siegbahn, and P,-0. Widmark, MOLCA. S, Version 4, Lund University, Sweden, 1997. 

Funetions with higher 1-values and with sizes more in line with those of the lower-1 orbitals are also used to introduee additional angular eorrelation into the ealeulation by permitting polarized orbital pairs (see Chapter 10) involving higher angular eorrelations to be formed. Optimal polarization funetions for first and seeond row atoms have been tabulated (B. Roos and P. Siegbahn, Theoret. Chim. Aeta (Berl.) 17, 199 (1970) M. J. Friseh, J. A. Pople, and J. S. Binkley, J. Chem. Phys., 3265 (1984)). 

A more detailed perturbation theory analysis leads to an improved correction formula. This method, known as the Davidson and Silver or Siegbahn correction, is... 

Even though Einstein developed the theory of the photoelectric effect in 1906 photoelectron spectroscopy, as we now know it, was not developed until the early 1960s, particularly by Siegbahn, Turner and Price. 

Figure 8.12 The He I ultraviolet photoelectron spectrum of benzene. (Reproduced from Karlsson, L., Mattsson, L., Jadmy, R., Bergmark, T. and Siegbahn, K., Physica Scripta, 14, 230, 1976)...

Figure 8.13 The MgATa oxygen Is and carbon Is X-ray photoelectron spectra of a 2 1 mixture of CO and CO2 gases. (Reproduced, with permission, from Allan, C. J. and Siegbahn, K. (November 1971), Publication No. UUIP-754, p. 48, Uppsala University Institute of Physics)...

Reproduced, with permission, from Siegbahn, K. (September 1975), Publication No. UUIP-909, p20 Uppsala University Institute of Physics]... 

Figure 8.15 The carbon Is X-ray photoelectron spectra of furan, pyrrole and thiophene. The sulphur Ip spectrum of thiophene is also shown. (Reproduced with permission from Gelius, U., Allan, C. J., Johansson, G., Siegbahn, H., Allison, D. A. and Siegbahn, K., Physica Scripta, 3, 237, 1971)...

Figure 8.17 A short, barely resolved, vibrational progression in the v- vibration of CHj in the carbon Is X-ray photoelecton spectrum of methane obtained with a monochromatized X-ray source. (Reproduced, with permission, from Gelius, U., Svensson, S., Siegbahn, H., Basilier, E., Faxalv, A. and Siegbahn, K., Chem. Phys. Lett, 28, 1, 1974)...

Figure 8.19 X-ray photoelectron spectrum, showing core and valence electron ionization energies, of Cu, Pd, and a 60% Cu and 40% Pd alloy (face-centred cubic lattice). The binding energy is the ionization energy relative to the Fermi energy, isp, of Cu. (Reproduced, with permission, from Siegbahn, K., J. Electron Spectrosc., 5, 3, 1974)...

Siegbahn, K., Nordling, C., Fahlman, A., Nordberg, R., Hamerin, K., Hedman, J., Johansson, G., Bergmark, T., Karlsson, S.-E., Lindgren, I. and Lindberg, B. (1967) Electron Spectroscopy for Chemical Analysis Atomic, Molecular, and Solid State Structure Studies by Means of Electron Spectroscopy, Almqvist and Wiksells, Uppsala. 

Xps was first successfully implemented for surface analysis by K. Siegbahn in the early 1950s. Much of the development of this approach for studyiag surfaces was subsequendy developed by this same group (20), and Siegbahn was awarded the Nobel Prize ia physics ia 1981 for these efforts. 

One other very important attribute of photoemitted electrons is the dependence of their kinetic energy on chemical environment of the atom from which they originate. This feature of the photoemission process is called the chemical shift of and is the basis for chemical information about the sample. In fact, this feature of the xps experiment, first observed by Siegbahn in 1958 for a copper oxide ovedayer on a copper surface, led to his original nomenclature for this technique of electron spectroscopy for chemical analysis or esca. 

M. Siegbahn (Uppsala) discoveries and researches in the field of X-ray spectroscopy. 

K. M. Siegbahn (Uppsala) development of high-resolution electron spectroscopy. N. Bloembergen (Harvard) and A. L. Schawlow (Stanford) development of laser spectroscopy. 

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