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[3] D. L. Mills, Physical Review B 62, 11197 (2000). [4] H. Höchst, and C.R. Ast,, Journal of Electron Spectr. and Relat. Phenomena, (in press) 2003 [5] C. R. Ast and H. Höchst, Physical Review Letter, in press (2003). [6] F. Patthey, W. D. Schneider, and H. Micklitz, Physical Review B 49, 11293 (1994). Fig. 1: Energy difference E 1 (filled dots) and relative peak intensity I 1 /I 0 (open dots) of the Bi 5d 5/2 component measured at h=60 eV as a function of parallel momentum along and . Fig. 2: Fermi level region of the projected bulk band structure of Bi(111). Arrows indicate indirect (I) and direct (D) interband transitions related to the loss features observed by LEELS.
THE P(1s) AND P(2p) XAFS SPECTRA OF ELEMENTAL PHOSPHORUS, THEORY AND EXPERIMENT Astrid Jürgensen Canadian Synchrotron Radiation Facility, Synchrotron Radiation Center, 3731 Schneider Drive, Stoughton, WI, USA 53589-3097 X-ray absorption spectroscopy was used to study the local structure and chemical bonding of elemental phosphorus. Three allotropes of this element exist in the solid state. Crystalline black- P, a semiconducting material with an orthorhombic puckered layer structure, is the most stable allotrope. White-P, the least stable allotrope, is composed of tetrahedral P 4 molecules. At room temperature it is a plastic crystal. Its structure is similar to -Mn with the P 4 molecules in the positions of the Mn atoms. The most common allotrope is the amorphous red-P. Like white-P it is composed of P 4 molecules. In the gas phase tetrahedral P 4 molecules are stable up to ~ 800 ºC. At higher temperatures they decompose into P 2 molecules that have a shorter P-P bond length and, like N 2 , a formal triple bond. Theoretical P(1s) and P(2p) XAFS spectra of gaseous and solid state phosphorus were calculated by ab initio FEFF and GSCF3 methods. These were compared and the spectral features were related to structural and electronic properties of the different allotropes of elemental phosphorus. The calculation results were then used to explain the features observed in the experimental P(1s) and P(2p) spectra of red-P, which were obtained at the DCM and Grasshopper beamlines of CSRF, respectively. They were measured simultaneously by total electron yield (TEY) and fluorescence yield (FY) with the incident photon beam at normal incidence to the sample surface. The results of this study were presented at the XAFS 12 conference, held in Malmö, Sweden in June of 2003. A paper has been submitted to Physica Scripta to be published in the conference proceedings. A temperature dependent P(1s) EXAFS study of red-P is in progress to determine the Debye-Waller factor (the mean square deviation of the interatomic distance) of the first coordination shell in red-P. 0.1 0.05 0 -0.05 -0.1 3 6 9 12 15 P4 molecule theory 0 1 2 3 4 5 6 0.35 P4 molecule 0.28 theory 0.21 0.14 0.07 (k) 0.1 0.05 0 -0.05 -0.1 0.1 0.05 0 -0.05 -0.1 white-P theory black-P theory FT(k 3 (k)) (Å -4 ) 0 0.28 0.21 0.14 0.07 0 0.28 0.21 0.14 0.07 white-P theory black-P theory 0.1 0.05 0 -0.05 red-P experiment 0 0.12 0.09 0.06 red-P experiment -0.1 0.03 3 6 9 12 15 k (Å -1 ) 0 0 1 2 3 4 5 6 R (Å) The experimental P(1s) (top) and P(2p) (bottom) XANES spectra of red-P The P(1s) EXAFS spectrum (left) and its Fourier Transform (right). The first peak in the FT represents the first coordination shell with an interatomic distance of 2.212 Å.
Page 2 and 3: Welcome to the 36 th SRC Users’ M
Page 4 and 5: 12:20 - 1:10 Lunch 1:10 -1:45 Poste
Page 6 and 7: Administration Executive Director D
Page 8 and 9: STATUS OF THE SRC BEAMLINES AND INS
Page 10 and 11: ACCELERATOR DEVELOPMENTS Ken Jacobs
Page 12 and 13: HIGH ENERGY RESEARCH POSSIBILITIES
Page 14 and 15: ATOMICALLY UNIFORM THIN FILMS ON SI
Page 16 and 17: calculated binding energies of the
Page 18 and 19: MANY-ELECTRON EFFECTS ON THE XE 5S
Page 20 and 21: PHOTOELECTRON SPECTROMETRY OF ATOMI
Page 22 and 23: PHOTOEMISSION STUDY OF USb AND UTe
Page 24 and 25: CANADIAN SYNCHROTRON RADIATION FACI
Page 26 and 27: SELF-ASSEMBLY OF BLOCK COPOLYMERS O
Page 28 and 29: A B S T R A C T S
Page 30 and 31: Photoemission spectra, a.u. -0.3 -0
Page 32 and 33: THE INITIAL AND FINAL STATE BANDS I
Page 34 and 35: TRANSITION LAYERS AT BURIED FERROMA
Page 36 and 37: LOW-DIMENSIONAL ELECTRONS AT SILICO
Page 38 and 39: SUBCELLULAR DISTRIBUTION OF MOTEXAF
Page 40 and 41: LINEAR POLARIZATION MEASUREMENTS OF
Page 42 and 43: Fig.1: Photoemission spectra of opt
Page 44 and 45: The sample manipulator has a cool d
Page 46 and 47: Cr and Fe but for these U systems t
Page 48 and 49: [4] G. -H. Gweon, J. W. Allen, and
Page 50 and 51: References [1] S. Cho, Y. Kim, A. D
Page 54 and 55: CHARACTERIZATION OF SULPHATE INTERA
Page 56 and 57: in the data acquisition chamber. Th
Page 58 and 59: spatially resolved chemistry of the
Page 60 and 61: THE RELATIONSHIP BETWEEN PHOSPHATE
Page 62 and 63: PHOTOEMISSION STUDIES OF QUANTUM WE
Page 64 and 65: Ag surface state such that it moves
Page 66 and 67: HIGH-RESOLUTION STUDY OF THE LITHIU
Page 68 and 69: RELATIVE PARTIAL CROSS SECTIONS AND
Page 70 and 71: Christian Ast Max-Planck Institute
Page 72 and 73: David L. Huber Physical Sciences La
Page 74 and 75: Tom Miller University of Illinois a
Page 76 and 77: Eric Wiedemann University of Wiscon
Page 78 and 79: Pete Hagen Phone: (608) 877-2154 Em
Page 80: NOTES

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