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Homer D. Hagstrum

Bio: Homer D. Hagstrum is an academic researcher. The author has contributed to research in topics: Molecular orbital & Auger effect. The author has an hindex of 1, co-authored 1 publications receiving 651 citations.

Papers
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Book
22 Dec 2012
TL;DR: In this paper, the authors present a review of the literature on electron spectroscopy and its application in the field of computer vision. But they do not discuss the specific applications of electron spectrograms.
Abstract: 1 Introduction.- 1. History.- 2. Scope of Present Book and Review of Past Books.- 3. Name-Calling.- 4. Areas Related to Electron Spectroscopy Not to be Discussed in Detail.- 4.1. Electron-Impact Spectroscopy.- 4.2. Photoemission.- 4.3. Penning Ionization Spectroscopy.- 4.4. Ion Neutralization Spectroscopy.- 5. Fields Related to Electron Spectroscopy.- 2 Instrumentation and Experimental Procedures.- 1. Source Volume.- 1.1. Excitation Devices.- 1.1.1. Electron Gun.- 1.1.2. X-Ray Tube.- 1.1.3. Synchrotron Radiation.- 1.1.4. Vacuum-UV Sources.- 1.2. Target Sample.- 1.2.1. Gases.- 1.2.2. Solids.- 1.2.3. Condensed Vapors, Liquids, and Targets at Other Than Room Temperature.- 1.3. Chamber for Angular Distribution Studies.- 1.4. Preacceleration and Deceleration.- 2. Analyzer.- 2.1. Cancellation of Magnetic Fields.- 2.1.1. Helmholtz Coils.- 2.1.2. Magnetic Shielding.- 2.2. Types of Analyzers.- 2.2.1. Retarding Grid.- 2.2.2. Dispersion.- 3. Detector Systems and Data Analysis.- 3.1. Single-Channel Detector.- 3.2. Position-Sensitive Detector.- 3.3. Scanning the Spectrum.- 3.4. Data Analysis.- 4. New Developments.- 5. Review of Commercial Instruments.- 5.1. AEI.- 5.2. Du Pont.- 5.3. Hewlett-Packard.- 5.4. McPherson.- 5.5. Perkin-Elmer.- 5.6. Physical Electronics.- 5.7. McCrone-RCI.- 5.8. Vacuum Generators, Inc..- 5.9. Varian.- 5.10. Others.- 3 Fundamental Concepts.- 1. Photoelectric Effect.- 2. Binding Energy.- 3. Final States and the Sudden Approximation.- 3.1. Spin-Orbit Splitting.- 3.2. Multiplet Splitting.- 3.3. Jahn-Teller Splitting.- 3.4. Electron Shakeoff and Shakeup.- 3.5. Configuration Interaction.- 3.6. Koopmans' Theorem and the Sudden Approximation.- 3.7. Vibrational and Rotational Final States.- 4. Atomic Wave Functions.- 5. Molecular Orbital Theory.- 5.1. Theoretical Models.- 5.1.1. Ab Initio Calculations.- 5.1.2. Semiempirical Calculations.- 5.2. Basis Set Extension and MO Mixing.- 5.3. Atomic and Molecular Orbital Nomenclature.- 5.3.1. Atoms.- 5.3.2. Molecules.- 4 Photoelectron Spectroscopy of the Outer Shells.- 1. Introduction.- 2. Energy Level Scheme.- 2.1. Binding Energy.- 2.2. Final States.- 2.2.1. Spin-Orbit Splitting.- 2.2.2. Multiplet Splitting due to Spin Coupling.- 2.2.3. Jahn-Teller Effect.- 2.2.4. Electron Shakeoff and Shakeup.- 2.2.5. Configuration Interaction.- 2.2.6. Resonance Absorption.- 2.2.7. Collision Peaks.- 3. Identification of the Orbital.- 3.1. Ionization Potentials.- 3.1.1. Characteristic Ionization Bands.- 3.1.2. Effects of Substituents.- 3.1.3. Sum Rule.- 3.1.4. The Perfluoro Effect.- 3.1.5. Dependence on Steric Effects.- 3.2. Identification of Orbitals by Vibrational Structure.- 3.3. Identification of Molecular Orbitals from Intensities of Ionization Bands.- 3.4. Identification of Molecular Orbitals by Angular Distribution.- 4. Comparison of PESOS with Other Experimental Data.- 4.1. Optical Spectroscopy.- 4.2. Mass Spectroscopy.- 5. Survey of the Literature on PESOS.- 5.1. Atoms.- 5.2. Diatomic Molecules.- 5.2.1. H2.- 5.2.2. N2 and CO.- 5.2.3. O2 and NO.- 5.2.4. Diatomic Molecules Containing Halogen.- 5.3. Triatomic Molecules.- 5.3.1. Linear Triatomic Molecules.- 5.3.2. Bent Triatomic Molecules.- 5.4. Organic Molecules.- 5.4.1. Methane, Alkanes, and Tetrahedral Symmetry.- 5.4.2. Unsaturated Aliphatics.- 5.4.3. Ring Compounds.- 5.4.4. Multiring Compounds.- 5.4.5. Organic Halides.- 5.4.6. Miscellaneous Organic Compounds Containing Oxygen, Nitrogen, Sulfur, and Phosphorus.- 5.5. Organometallics and Miscellaneous Inorganic Polyatomic Molecules.- 5.6. Ions, Transient Species, and Other Special Studies in PESOS.- 6. Studies on Solids.- 7. Analytical Applications of PESOS.- 5 Photoelectron Spectroscopy of the Inner Shells.- 1. Atomic Structure.- 2. Theoretical Basis of Chemical Shifts of Core Electrons.- 2.1. Valence Shell Potential Model.- 2.2. Effect of Neighboring Atoms.- 2.3. Calculation of Net Charge from Electronegativity.- 2.4. Calculation of Net Charge from Semiempirical MO.- 2.5. Use of Ab Initio Calculations for Chemical Shifts.- 2.6. Correlation of Chemical Shift with Thermochemical Data.- 3. Summary of Data on Chemical Shifts as a Function of the Periodic Table.- 3.1. Carbon.- 3.2. Nitrogen and Phosphorus.- 3.3. Sulfur and Oxygen.- 3.4. Group IIIA, IVA, VA, and VIA Elements.- 3.4.1. Group IIIA: B, Al, Ga, In, and Tl.- 3.4.2. Group IVA: C, Si, Ge, Sn, and Pb.- 3.4.3. Group VA: N, P, As, Sb, and Bi.- 3.4.4. Group VIA: O, S, Se, and Te.- 3.5. Halides and Rare Gases.- 3.6. Alkali Metals and Alkaline Earths.- 3.7. Transition Metals.- 3.7.1. First Transition Metal Series: Sc, Ti, V, Cr, Mn, Fe, Co, Ni.- 3.7.2. Second Transition Metal Series: Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd.- 3.7.3. Third Transition Metal Series: Hf, Ta, W, Re, Os, Ir, Pt.- 3.8. Groups IB and IIB: Cu, Ag, Au, Zn, Cd, Hg.- 3.9. Rare Earths and Actinides.- 4. Special Topics on Shifts in Core Binding Energies.- 4.1. Experimental and Interpretive Problems in PESIS.- 4.1.1. Comparative Problems in the Gas and Solid Phases.- 4.1.2. Charging.- 4.1.3. Definition of Binding Energy for Insulators.- 4.1.4. Binding Energy of Surface Atoms.- 4.1.5. Radiation Effects.- 4.1.6. Linewidths.- 4.2. Inorganic Compounds.- 4.2.1. Multiple Chemical Environment.- 4.2.2. Coordination Complexes.- 4.3. Organic Compounds.- 4.3.1. Resonance.- 4.3.2. Substituent Effects.- 4.3.3. Group Analysis.- 4.3.4. Specific Studies on Organic Molecules.- 4.4. Comparison of Core Electron Binding Energy Shifts with Other Physical Quantities.- 4.4.1. Mossbauer Isomer Shift.- 4.4.2. NMR.- 4.4.3. Other Physical Data.- 5. Other Applications of PESIS.- 5.1. Multicomponent Structure.- 5.1.1. Multiplet or Exchange Splitting.- 5.1.2. Electron Shakeoff and Shakeup.- 5.1.3. Configuration Interaction.- 5.1.4. Characteristic Energy Losses.- 5.1.5. Determining the Nature of Multicomponent Structure.- 5.2. PESIS for Surface Studies.- 5.3. Angular Studies with PESIS.- 6. Use of PESIS for Applied Research.- 6.1. PESIS as an Analytical Tool.- 6.2. Biological Systems.- 6.3. Geology.- 6.4. Environmental Studies.- 6.5. Surface Studies.- 6.6. Polymers and Alloys.- 6.7. Radiation Studies.- 6.8. Industrial Uses.- 6 Auger Electron Spectroscopy.- 1. Theory of the Auger Process.- 2. Comparison of the Auger Phenomenon with the Photoelectric Effect and X-Ray Emission.- 3. Use of Auger Spectroscopy for Gases.- 3.1. Atoms.- 3.2. Molecules.- 3.3. Study of Ionization Phenomena by Auger Spectroscopy.- 3.4. Autoionization.- 3.5. Auger Spectroscopy for Use in Gas Analysis.- 4. Use of Auger Spectroscopy in the Study of Solids.- 4.1. Special Problems Encountered on Using AES with Solids.- 4.1.1. Variables Concerned with Production of Auger Electrons.- 4.1.2. High-Energy Satellite Lines.- 4.1.3. Characteristic Energy Losses.- 4.1.4. Charging in Nonconducting Samples.- 4.2. High-Resolution Auger Spectroscopy with Solids.- 4.3. General Analytical Use of Auger Spectroscopy.- 4.4. Use of Auger Spectroscopy in the Study of Surfaces.- 4.4.1. General Considerations.- 4.4.2. Literature Survey of Surface Applications.- 4.5. Other Methods for Surface Analysis.- 4.5.1. Comparison of PESIS and Auger Spectroscopy for Surface Studies.- 4.5.2. Methods of Surface Analysis Other than AES and PESIS.- Appendixes.- 1. Atomic Binding Energies for Each Subshell for Elements Z = 1-106.- 3. Compilation of Data on Shifts in Core Binding Energies.- 4. Acronyms and Definitions of Special Interest in Electron Spectroscopy.- References.

661 citations


Cited by
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Journal ArticleDOI
TL;DR: A review of the most recent ARPES results on the cuprate superconductors and their insulating parent and sister compounds is presented in this article, with the purpose of providing an updated summary of the extensive literature.
Abstract: The last decade witnessed significant progress in angle-resolved photoemission spectroscopy (ARPES) and its applications. Today, ARPES experiments with 2-meV energy resolution and $0.2\ifmmode^\circ\else\textdegree\fi{}$ angular resolution are a reality even for photoemission on solids. These technological advances and the improved sample quality have enabled ARPES to emerge as a leading tool in the investigation of the high-${T}_{c}$ superconductors. This paper reviews the most recent ARPES results on the cuprate superconductors and their insulating parent and sister compounds, with the purpose of providing an updated summary of the extensive literature. The low-energy excitations are discussed with emphasis on some of the most relevant issues, such as the Fermi surface and remnant Fermi surface, the superconducting gap, the pseudogap and $d$-wave-like dispersion, evidence of electronic inhomogeneity and nanoscale phase separation, the emergence of coherent quasiparticles through the superconducting transition, and many-body effects in the one-particle spectral function due to the interaction of the charge with magnetic and/or lattice degrees of freedom. Given the dynamic nature of the field, we chose to focus mainly on reviewing the experimental data, as on the experimental side a general consensus has been reached, whereas interpretations and related theoretical models can vary significantly. The first part of the paper introduces photoemission spectroscopy in the context of strongly interacting systems, along with an update on the state-of-the-art instrumentation. The second part provides an overview of the scientific issues relevant to the investigation of the low-energy electronic structure by ARPES. The rest of the paper is devoted to the experimental results from the cuprates, and the discussion is organized along conceptual lines: normal-state electronic structure, interlayer interaction, superconducting gap, coherent superconducting peak, pseudogap, electron self-energy, and collective modes. Within each topic, ARPES data from the various copper oxides are presented.

3,077 citations

Journal ArticleDOI
TL;DR: The first application of a new COF material, COF-LZU1, for highly efficient catalysis, which possesses a two-dimensional eclipsed layered-sheet structure, making its incorporation with metal ions feasible.
Abstract: Covalent organic frameworks (COFs) are crystalline porous solids with well-defined two- or three-dimensional molecular structures. Although the structural regularity provides this new type of porous material with high potentials in catalysis, no example has been presented so far. Herein, we report the first application of a new COF material, COF-LZU1, for highly efficient catalysis. The easily prepared imine-linked COF-LZU1 possesses a two-dimensional eclipsed layered-sheet structure, making its incorporation with metal ions feasible. Via a simple post-treatment, a Pd(II)-containing COF, Pd/COF-LZU1, was accordingly synthesized, which showed excellent catalytic activity in catalyzing the Suzuki-Miyaura coupling reaction. The superior utility of Pd/COF-LZU1 in catalysis was elucidated by the broad scope of the reactants and the excellent yields (96-98%) of the reaction products, together with the high stability and easy recyclability of the catalyst. We expect that our approach will further boost research on designing and employing functional COF materials for catalysis.

1,748 citations

01 Jan 2009
TL;DR: The PENELOPE as mentioned in this paper computer code system performs Monte Carlo simulation of coupled electron-photon transport in arbitrary materials for a wide energy range, from a few hundred eV to about 1 GeV.
Abstract: The computer code system PENELOPE (version 2008) performs Monte Carlo simulation of coupled electron-photon transport in arbitrary materials for a wide energy range, from a few hundred eV to about 1 GeV. Photon transport is simulated by means of the standard, detailed simulation scheme. Electron and positron histories are generated on the basis of a mixed procedure, which combines detailed simulation of hard events with condensed simulation of soft interactions. A geometry package called PENGEOM permits the generation of random electron-photon showers in material systems consisting of homogeneous bodies limited by quadric surfaces, i.e., planes, spheres, cylinders, etc. This report is intended not only to serve as a manual of the PENELOPE code system, but also to provide the user with the necessary information to understand the details of the Monte Carlo algorithm.

1,675 citations

Book
29 Apr 1988
TL;DR: Physics at Surfaces as discussed by the authors is a unique graduate-level introduction to the physics and chemical physics of solid surfaces and atoms and molecules that interact with solid surfaces, and it provides a synthesis of the entire field of surface physics from the perspective of a modern condensed matter physicist with a healthy interest in chemical physics.
Abstract: Physics at Surfaces is a unique graduate-level introduction to the physics and chemical physics of solid surfaces, and atoms and molecules that interact with solid surfaces. A subject of keen scientific inquiry since the last century, surface physics emerged as an independent discipline only in the late 1960s as a result of the development of ultra-high vacuum technology and high speed digital computers. With these tools, reliable experimental measurements and theoretical calculations could at last be compared. Progress in the last decade has been truly striking. This volume provides a synthesis of the entire field of surface physics from the perspective of a modern condensed matter physicist with a healthy interest in chemical physics. The exposition intertwines experiment and theory whenever possible, although there is little detailed discussion of technique. This much-needed text will be invaluable to graduate students and researchers in condensed matter physics, physical chemistry and materials science working in, or taking graduate courses in, surface science.

1,636 citations

Journal ArticleDOI
TL;DR: In this article, the authors calculated the X-ray photoelectron spectra (XPS) of Mn 21,M n 31, and Mn 41 free ions and showed that these ions adopt high spin states in MnO, manganite, and birnessite.
Abstract: Calculated Mn(2p3/2) X-ray photoelectron spectra (XPS) of Mn 21 ,M n 31 , and Mn 41 free ions are strikingly similar to Mn(2p 3/2) spectra of Mn 21 -, Mn 31 -, and Mn 41 -oxides and oxyhydroxides, indicating that these ions adopt high spin states in MnO, manganite, and birnessite. The Mn(2p) peak structures reveal the presence of only Mn 31 in manganite, but Mn 21 ,M n 31 , and Mn 41 are present in the near-surface of synthetic birnessite at about 5, 25, and 70%, respectively. Precipitation of birnessite by reaction of Mn 21 (aq) with an

897 citations