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Inorganic nanostructures
Inorganic nanostructures

... tubes have diameters of the order of 1-2 nm. The confinement effects can here be seen as the adjustment of electronic wavefunctions to fit to the circumfence of the tube. It should be noted that many applications of nanostructures do not depend directly on size effects on electronic properties. Inst ...
to the fiftieth anniversary of starting up the first linear acc
to the fiftieth anniversary of starting up the first linear acc

SCATTERING OF ELECTRONS BY DIATOMIC MOLECULES IN
SCATTERING OF ELECTRONS BY DIATOMIC MOLECULES IN

Advanced Physical Chemistry
Advanced Physical Chemistry

Florida`s - Wavefunction, Inc.
Florida`s - Wavefunction, Inc.

Historical overview of the developments of quantum mechanics
Historical overview of the developments of quantum mechanics

... certain materials, particularly diamond (carbon), boron and silicon. The carbon anomaly had been known since 1841. In experiments published in 1905 it was shown by the Scottish chemist James Dewar that the heat capacity of diamond essentially vanishes near 20 K, and as the temperature of any materia ...
Document
Document

... INTRODUCTION: The overview of the “Why, Where, and What” of bonding It is important that atoms bond. Why? Because they need to bond in order to make _____________, _______________, and other more complex forms of matter. For example, if atoms didn’t bond, you would be quite thirsty all the time! Yes ...
Chemistry 3211 – Coordination Chemistry Part 4 Electronic Spectra
Chemistry 3211 – Coordination Chemistry Part 4 Electronic Spectra

... way of writing electron configurations that allows us to not only describe the ground state, but any possible excited states as well. We can do this by describing the electronic state according to its orbital and spin degeneracy. For two electrons in a p orbital, we can say that electron 1 will have ...
chapt 2
chapt 2

... When these bonds are broken, the energy that is released can be used by the cell to do work. Phosphorylation reactions are commonly used to transfer potential energy. ...
Lecture 7: Stationary Perturbation Theory In most practical
Lecture 7: Stationary Perturbation Theory In most practical

... coefficients cαβ . The 1st order energy shift a1α here plays the role of an eigenvalue. The characteristic equation of (22) is a polynomial of order f in a1α so that we can expect up to f different roots, each root corresponding to one value of α. If all roots are different one says that the degener ...
Laser - nptel
Laser - nptel

... of a lower lying level (could be the ground state) is incident on the atom. The incident photon induces the electron in the excited state to make a transition to the lower level by emission of a photon. The emitted photon travels in the same direction as the incident photon. Significantly, the new p ...
cond-mat/0205001 PDF
cond-mat/0205001 PDF

... been calculated6,7 in the self-consistent Born approximation (SCBA) and has been studied experimentally2–5,8–11 through measurements of the magnetoconductivity. We report magnetoconductivity measurements from an extremely low density, ∼ 1.9 x109 m−2 , where e-e interactions are negligible, to densit ...
Chemistry Review
Chemistry Review

... Fluids – gases and liquids, flow Ideal gas – imaginary gas that fits all the assumptions of the kinetic molecular theory Kelvin – SI unit of temperature Kinetic Theory- group of ideas explaining the interaction of matter and energy due to particle motion Melting – change in state from a solid to a l ...
CHM2C1-B Physical Spectroscopy
CHM2C1-B Physical Spectroscopy

Chapter 2 Motion Along a Straight Line Position, Displacement
Chapter 2 Motion Along a Straight Line Position, Displacement

... Topic 6.2 Extended E – Equipotential surfaces Suppose we have two parallel plates separated by 15 mm and charged by a 9 V battery. (a) How far apart would the equipotential surfaces be between the plates, if their potential difference was to be 0.10 V? Since the electric field is constant between t ...
Extension of the Homogeneous Electron Gas Theory to First
Extension of the Homogeneous Electron Gas Theory to First

... The state density and the carrier density obtained by the FOHEG theory are expressed by formulae given by Eqs. (17) and (18), respectively. These expressions reduce to the flat-band equations frequently encountered in standard textbooks when the electric field approaches zero. The density of states ...
Unit 1 Notes (general chem review)
Unit 1 Notes (general chem review)

...  periods: numbered up and down, but run across the table…always number from very left hand side or the very right hand side. There are SEVEN periods.  Numbering of groups  groups: numbered left to right, but run up and down in the table…number from H to He—18 groups. The intertransition metals do ...
From Last Time… Energy levels Emitting and absorbing light
From Last Time… Energy levels Emitting and absorbing light

Unit 1 Powerpoint
Unit 1 Powerpoint

... Scientists show the composition of compounds by a kind of shorthand known as a chemical formula. Water, which contains two atoms of hydrogen for each atom of oxygen, has the chemical formula =H2O. The formula for table salt, NaCl, indicates that the elements that make up table salt—sodium and chlori ...
Quantum Numbers and Orbitals
Quantum Numbers and Orbitals

How do you tell if a molecule is paramagnetic or diamagnetic
How do you tell if a molecule is paramagnetic or diamagnetic

... oxygen for example. According to VB theory, each oxygen atom has 3 sp2 hybrid orbitals, there is one sigma-bond formed by the overlap of a pair of sp2 hybrid orbitals from each atom, one pi-bond formed by the overlap of atomic p-orbitals and each oxygen atom has 2 non-bonding pairs in 2 sp2 hybrid o ...
The Quantized Hall Effect
The Quantized Hall Effect

... tion perpendicularboth to their origi- increase.The reason is that the "drift fully reliable,it is nonethelesseffective nal directionand to that of the magnet- velocity" with which the guiding cen- as a guide that suggeststhe general ic field: they will move toward the top ter of each electron's cyc ...
chapter
chapter

Part II - Web site of Dr. Charles Berks
Part II - Web site of Dr. Charles Berks

... crystal from their positions in the lattice to an infinite separation in the gaseous state. That is MX(s)  M+(g) + X-(g). Both definitions result in a lattice energy of the same magnitude but of opposite sign. The definition used by our textbook is that given above and always results in a negative ...
Quantum entanglement between the electron clouds of nucleic acids
Quantum entanglement between the electron clouds of nucleic acids

... The precise value of energy levels is of crucial importance for any kind of interaction in physics. This is also true for processes in biological systems. It has recently been shown for the photosynthesis complex FMO [2–5] that maximum transport efficiency can only be achieved when the environment b ...
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X-ray photoelectron spectroscopy



X-ray photoelectron spectroscopy (XPS) is a surface-sensitive quantitative spectroscopic technique that measures the elemental composition at the parts per thousand range, empirical formula, chemical state and electronic state of the elements that exist within a material. XPS spectra are obtained by irradiating a material with a beam of X-rays while simultaneously measuring the kinetic energy and number of electrons that escape from the top 0 to 10 nm of the material being analyzed. XPS requires high vacuum (P ~ 10−8 millibar) or ultra-high vacuum (UHV; P < 10−9 millibar) conditions, although a current area of development is ambient-pressure XPS, in which samples are analyzed at pressures of a few tens of millibar.XPS is a surface chemical analysis technique that can be used to analyze the surface chemistry of a material in its as-received state, or after some treatment, for example: fracturing, cutting or scraping in air or UHV to expose the bulk chemistry, ion beam etching to clean off some or all of the surface contamination (with mild ion etching) or to intentionally expose deeper layers of the sample (with more extensive ion etching) in depth-profiling XPS, exposure to heat to study the changes due to heating, exposure to reactive gases or solutions, exposure to ion beam implant, exposure to ultraviolet light.XPS is also known as ESCA (Electron Spectroscopy for Chemical Analysis), an abbreviation introduced by Kai Siegbahn's research group to emphasize the chemical (rather than merely elemental) information that the technique provides.In principle XPS detects all elements. In practice, using typical laboratory-scale X-ray sources, XPS detects all elements with an atomic number (Z) of 3 (lithium) and above. It cannot easily detect hydrogen (Z = 1) or helium (Z = 2).Detection limits for most of the elements (on a modern instrument) are in the parts per thousand range. Detection limits of parts per million (ppm) are possible, but require special conditions: concentration at top surface or very long collection time (overnight).XPS is routinely used to analyze inorganic compounds, metal alloys, semiconductors, polymers, elements, catalysts, glasses, ceramics, paints, papers, inks, woods, plant parts, make-up, teeth, bones, medical implants, bio-materials, viscous oils, glues, ion-modified materials and many others.XPS is less routinely used to analyze the hydrated forms of some of the above materials by freezing the samples in their hydrated state in an ultra pure environment, and allowing or causing multilayers of ice to sublime away prior to analysis. Such hydrated XPS analysis allows hydrated sample structures, which may be different from vacuum-dehydrated sample structures, to be studied in their more relevant as-used hydrated structure. Many bio-materials such as hydrogels are examples of such samples.
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