In ultraviolet photoelectron spectroscopy, why is the fermi level of a metal observed as a distinct cutoff?

From my understanding, the fermi level of a metal at room temperature indicates an energy level at which 50% of electrons exist above, and 50% exist below. Why then, is the fermi level in UPS spectra of metals observed as a distinct cutoff point? It seems like it should be continuous.

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The effectiveness of carbon dioxide snow cleaning has been demonstrated via light microscopy, particle counting, scanning electron microscopy, microprobing, X-ray photoelectron spectroscopy, atomic-force microscopy, and mass spectroscopy. en.wikipedia.org/wiki/Car…
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A new method for identifying quantum orbits enables photoelectron spectroscopy via tunneling ionization to provide attosecond temporal and subangstrom spatial resolution measurement of electron dynamics. spie.org/news/decoding-el…
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πŸ‘€︎ u/PhotonicsWest
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[College Chemistry 101] Calculate Zeff for electron, using photoelectron spectroscopy?

Hello, I have no idea on how to do this problem. I'd really appreciate someone showing me how to do this, you can change the element/numbers. Thanks in advance.

Here's what's being asked -

Using photoelectron spectroscopy, the ionization energy of the least tightly bound valence electron on Cl was determined to be 13.0 eV.

Calculate the Zeffective for this electron

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πŸ‘€︎ u/EthanMLego33
πŸ“…︎ Sep 25 2020
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X-Ray Photoelectron Spectroscopy: Peaks VS "ground level"

Hello. I was wondering why on an XPS graph (with # emitted electrons vs the binding energy) why there seems to be emitted electrons that don't correspond exactly to an electron energy shell level.

This wikipedia article has some neat images I refer to:

https://en.wikipedia.org/wiki/X-ray_photoelectron_spectroscopy

In the second image labelled "XPS physics - the photoelectric effect*.",* you see a graph with peaks corresponding to particular electron shells, but there's also "mounds" that these peaks rest on.

I was really curious why the mounds seemed to go up and down. Do these mounds correspond to auger electron emissions (i.e "leftover" energy is going into these electrons after a higher energy electron is released and the core shell is filled again?)

Thanks for any response to my perhaps naive question!

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πŸ“…︎ Oct 14 2020
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[ASAP] Correlating the Influence of Disulfides in Monolayers across Photoelectron Spectroscopy Wettability and Tunneling Charge-Transport

Journal of the American Chemical SocietyDOI: 10.1021/jacs.0c06508

https://ift.tt/3hsAGz5

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Massive growth of X-ray Photoelectron Spectroscopy (XPS) Market 2025 with high CAGR in Coming Years with Focusing Key players like Kratos Analytical, ThermoFisher Scientific, ULVAC, etc.

https://preview.redd.it/lbsbbgampem41.jpg?width=700&format=pjpg&auto=webp&s=cd06cb5255966c5d90fdfc93b1148c932bbdb223

Is X-ray Photoelectron Spectroscopy (XPS) Market Trapped Between Growth Expectations and Uncertainty?

The Global X-ray Photoelectron Spectroscopy (XPS) Market Report 2020-2025 includes a comprehensive analysis of the present Scenario of the industry. It specifies the X-ray Photoelectron Spectroscopy (XPS) Market size and also factors controlling the growth of the market. The report starts with the basic X-ray Photoelectron Spectroscopy (XPS) market industry overview and then goes into minute details of the X-ray Photoelectron Spectroscopy (XPS) market.

The X-ray Photoelectron Spectroscopy (XPS) market Report contains in depth information of major drivers, opportunities, challenges, industry trends and their impact on the market. The X-ray Photoelectron Spectroscopy (XPS) Market report also provides data about the company and its operations. This report also provides information on the Pricing Strategy, Brand Strategy, Target Client of the X-ray Photoelectron Spectroscopy (XPS) Market. Also provides Distributors/Traders List offered by the company. This research report also involves key competition, market trends with forecast over the predicted years, anticipated growth rates. The primary factors driving and impacting growth market data and analytic are derived from a combination of primary and secondary sources.

***To understand the outline of the report, get the sample copy of this report: @***https://www.acquiremarketresearch.com/sample-request/285953/

In-depth analysis of X-ray Photoelectron Spectroscopy (XPS) market research report offers an forecast period 2020–2025, detail study on market trends and the present-future market state of the X-ray Photoelectron Spectroscopy (XPS) market across the globe with valuable facts and figures. X-ray Photoelectron Spectroscopy (XPS) Market also provides data concerning the rising opportunities within the X-ray Photoelectron Spectroscopy (XPS) market, Trends technologies that may boost these growth trends. X-ray Photoelectron Spectroscopy (XPS) Market report contains a comprehensive summary of X-ray Photoelectron Spectroscopy (XPS) together with defi

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Attosecond Photoelectron Spectroscopy Accelerated - Laser physicists have succeeded in reducing the acquisition time for data required for reliable characterization of multidimensional electron motions by a factor of 1000 mpq.mpg.de/5804833/2019-0…
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πŸ‘€︎ u/HearTomorrow
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X-Ray Photoelectron Spectroscopy Market worth over $775mn by 2023

​The X-Ray Photoelectron Spectroscopy Market to exceed USD 775 million by 2023 as per a new research report.

Growing application of x-ray photoelectron spectroscopy in drug safety and research and favorable reimbursement policies should drive industry growth over the forecast period. Government initiatives to spread awareness regarding contamination of drugs and its formulation, R&D and chemical analysis should further drive x-ray photoelectron spectroscopy market growth.

Advancement in technology and accuracy, highly reliable x-ray photoelectron spectroscopes and easy availability should drive business growth. Furthermore, introduction of numerous hyphenated technologies by most of the companies to address complex analytical applications should accelerate demand for x-ray photoelectron spectroscopy. The lack of technical labour force and growing competition from advanced technologies may restrain x-ray photoelectron spectroscopy market growth.

Request for a sample of this research report @ https://www.gminsights.com/request-sample/detail/431

Government initiatives such as "Drug Safety Information Survey" organized by Health Canada and "Safe Use Initiative" by FDA are raising awareness regarding medical R&D, this will offer producers with lucrative growth opportunities over the forecast timeframe.

Healthcare industry accounted for significant growth over the forecast period. The growing research in spatial control of biomolecules and cells for applications like array technologies and tissue engineering is attributed for its high use. Increasing 3D printing organs and packaging applications in healthcare industry should further drive x-ray photoelectron spectroscopy market growth.

Hard x-ray photoelectron spectroscopy (HAXPES) is the high energy variant of x-ray photoelectron spectroscopy (XPS) was recently developed. It is used in the study of several semiconductor material systems which will drive industry growth over the forecast period.

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Contamination detection is the fastest growing use due to growing demand from semiconductors, pharmaceutical, biotechnology and electronic industry. The growth is attributed due to increase

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πŸ“…︎ Sep 17 2018
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Does anyone have an old MIT photoelectron spectroscopy video that's since been removed?

There is an old video that was on YouTube of an MIT professor explaining PES and it's since been removed. It was a great explanation and now it's gone! All I remember is that he had about 9 chalkboards going at once, moving them up and down, and he draw a picture of the PES device. I'd love to have this file.

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πŸ“…︎ Oct 12 2016
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In a photoelectron spectroscopy experiment, which values are known?

This is my understanding of it: A light (of energy hv) is shined onto a sample of gaseous atoms, which will absorb a certain amount of light (the ionization energy). The difference between the inputted light energy hv and the ionization energy is the kinetic energy that will be released with the electrons.

What I'm not as sure of: Scientists control the voltage of the analyzer (charged magnetic plates?) until the electrons hit the detector and they can measure the kinetic energy of the electrons. This would mean that in the formula hv=IE+KE, they know hv initially (since they control the amount of light?), they test for KE, and they calculate IE... Is this correct?

Edit: saw "photoelectron count rate" on the y-axis of a graph and KE (ev) on the x-axis and now I'm more confused- this means that they control the KE, but how does the # e-/sec give the IE of the gaseous atom?

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πŸ‘€︎ u/casualmania
πŸ“…︎ Nov 29 2017
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How is the X-ray source in an X-ray photoelectron spectroscopy system generated?

There may be several answers, but generally? And what elements are used to create this source? Thanks.

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πŸ“…︎ Jul 15 2012
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"EH2 - Branch B : HAXPES + SXRD" Hard X-Ray Photoelectron Spectroscopy experiment [960 x 720]
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Born today : April 20th - Kai Siegbahn, PhD, Physicist, Nobel Laureate, "for his contribution to the development of high-resolution electron spectroscopy", "developed the method of Electron Spectroscopy for Chemical Analysis (ESCA), now usually described as X-ray photoelectron spectroscopy" en.wikipedia.org/wiki/Kai…
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"EH2 - Branch B : HAXPES + SXRD" Hard X-Ray Photoelectron Spectroscopy experiment [960 x 720]
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Anyone here into background corrections in photoelectron spectroscopy?

Being fairly optimistic, I hope that someone here could actually help me.

Recently I came across some publications' experimental data that can actually fit my calculations. The catch is, that (I think) the photoelectron spectrum of the gold surface was not corrected for at all. I have no clue whatsoever on how to even start correcting for it, and if I do not correct for it I cannot really say if my calculations are on the spot.

Any one with experience care to point me in any direction?

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πŸ‘€︎ u/dr_bitz
πŸ“…︎ Nov 28 2010
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Is it feasible to make a small smartphone camera sensor that has high well capacity (100000+ photons), small pixels (<2 micron), has low power usage, and rely on photoelectron multiplication (or similar) that's continuously adjustable to cancel out noise (or ultra low read noise)?

For background, I do photography as a hobby, teach myself technical material, look for problems to solve, and brainstorm ideas for solutions.

Problem

Most people stick with their smartphones on the basis that the best camera is what you actually use. The problem is that while they've improved, they're still terrible in low light. People want to photograph both subjects with broad ratios between bright and dark as well as scenes that are more moderate or low in contrast ratio.

With video on a bright day, even moderate sensitivity levels like ISO 50 can be awkward because of wide aperture lenses. Under the "Sunny 16" rule, a wide aperture is difficult without low sensitivity and high well capacity to compensate.

With candlelight scenes with flames and areas reflecting off flames, high noise and blown out highlights are a given. With moonless nights lit only stars and no light pollution, even the ISO 4 million camera from Canon will scrape by. Inability to capture starry moonless on smartphones is a given.

If fewer photons are collected but the read noise is the same, low light performance and dynamic range can degrade.

Ideas

There are solutions I looked at for this challenge. They are:

  1. OPF CMOS. If I understand correctly, the voltage gets adjusted as a way of adjusting sensitivity. The one Panasonic is working on has a "high" full well capacity. How does this compare to avalanche gain?
  2. QIS CMOS. With combining single bit values for picture construction, how can it handle bursts from strobes and xenon flash units? How can the processor handle the high volume of data generated compared to regular CMOS (if it does create a high volume of data)?

What're your thoughts?

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Why didn't Gamu stay using Photoelectron tube for transformation?
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