Questions tagged [atomic-physics]
Atomic physics is the field of physics that studies atoms as an isolated system of electrons and an atomic nucleus. It is primarily concerned with the arrangement of electrons around the nucleus and the processes by which these arrangements change. This includes ions as well as neutral atoms and, unless otherwise stated, for the purposes of this discussion it should be assumed that the term atom includes ions.
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Does spectroscopy count as a measurement of electron spin?
There was some debate in my modern physics course about the statement
"The spin of an electron can only be measured in the presence of an external magnetic field".
So far in the course, ...
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Potential energy stored in the electron of the first and the second ionisation and the distinction between them
After getting this answer
You have to do work when removing the electron from the atom, which is the potential energy gained in the system, and you lose this potential energy when you "reunite&...
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Where Is the Potential Energy Stored in an Ionized Atom?
In its original usage, potential energy refers to the increase in a system’s energy when a mass is lifted in a gravitational field.
By analogy, the concept also applies to removing an electron from an ...
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How Is the Mass Defect Distributed Among the Electron, Proton, and Neutron? [closed]
The reduction in mass associated with the capture of an electron by an ion can be measured experimentally using high-precision mass spectrometry techniques such as those implemented in advanced ...
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Why are there no $\rm Si$ $3p$ peaks in XPS spectra of Silicon?
In XPS spectra of Silicon we only see $\rm Si$ $2s$ and $\rm Si$ $2p$ peaks. Why no $\rm Si$ $3s$ or $\rm Si$ $3p$ peaks? Silicon has electrons in both the $3s$ and $3p$ orbitals that could be emitted ...
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Why is the electron probability density finite at the nucleus despite the Coulomb potential being singular?
In the hydrogen atom, the Coulomb potential
$$V(r) = -\frac{e^{2}}{4\pi\varepsilon_0 r}$$
$$\psi_{1s}(0)=\frac{1}{\sqrt{\pi a_0^3}}$$
This seems contradictory: how can the electron have non-zero ...
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Zeeman splitting of Mercury green (546 nm) line: why no spin-orbit?
I'm teaching the Zeeman Effect and have gone through books and other lecture notes. I understand why, for the sodium D-line, we need to include spin-orbit coupling and then apply the Zeeman shift to ...
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How does heat affect atoms? [duplicate]
I was thinking about this, and originally I thought that heat was just the movement of things... but it's not. And I was thinking about heat in general, what is it, is it like... a movement of atoms (...
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How is the separation between core and valence electrons justified?
The full crystal Hamiltonian, strictly speaking, depends on all electrons, protons, and neutrons. Even before applying the Born–Oppenheimer approximation, one typically assumes — implicitly — that the ...
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Why I am not expanding? [duplicate]
We know universe is expanding and space is also expanding.
When why we dont feel the space around us and ourself expanding or stretching .even an big object
Does it negligible?
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Meaning of band gap structure [closed]
In a hydrogen atom, the electron can take only certain energies (quantized energies) only. When two hydrogen atoms come close, the electrons can take up more energy states but still the states are ...
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Why are the principal quantum number $n$, orbital angular momentum quantum number $l$, and magnetic quantum number $m$ so important for hydrogen atom?
They commute with each other and are therefore good quantum numbers. Furthermore, the energy is the eigenvalue in the time-independent Schrödinger equation. But are there other reasons I missed?
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Atomic orbitals of elements
Why is the sequence of atomic orbitals (1s, 2s, 2p, 3s, 3p, 4s, 3d, …) the same for all elements, cf. the Aufbau principle, even though different elements have different numbers of electrons?
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Can the spin of a free electron be determined from the Stern-Gerlach experiment?
If free charged electrons would pass through the inhomogeneous field, would they experience a deflection that could help determine their spin and exhibit two fringes on the detector sheet? Is the ...
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Spontaneous Emission spectrum in a non-magic potential
I want to understand the effect of differential light shift (caused by a non-magic potential) on the spontaneous emission spectrum of a two-level system .
In particular, if the SE spectrum of the ...
