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, ...

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61 views

What is an object made of? [duplicate]

If object made of atoms and atoms are invisible then when we look at an object or touch an object what we see or feel?
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226 views

By what mechanism is a photon emitted or absorbed in atomic electron state transitions?

I understand atomic emission and absorption spectra well - photons of a specific energy can be emitted or absorbed by atoms, if that energy corresponds perfectly to the energy difference between two ...
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596 views

How can light emit three kinds of spectra?

In case of black-body radiation, radiation gives continuous spectra. Molecular spectra is an example of band spectra. Similarly, there's also the atomic spectra. Why are the spectra of light not same ...
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1answer
150 views

Fusion, Magnets and Quantum Generators [closed]

I cannot even play like I'm even at this level, but this is the fusion reactor in Germany called the Wendelstein 7-X stellarator. These doughnut-shaped magnets (often seen on Physic Exchange) are ...
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62 views

Are atoms elementary? [closed]

I'm reading wikipedia about Real neutral particle. I know, there are many different particles discovered in the background of atom, which was ( Neutrons + Protons + Electrons ) before. For example, ...
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1answer
51 views

Which electron is first ionized $n=2,\ell=1, m=?$ [closed]

Eletrons in atoms are described by n,l, m, s quantum numbers? For noble gas 1s2 2s2 2p6 which is the first electron that will be ionized n=2, l=1, m=?, s = ?
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40 views

Multi-photon excitation probability for a two-level system

If a two-level system with a lifetime $\tau$ is excited with a pulse of duration $t_{pulse}$, what is the probability of exciting more than one photon? For simplicity we can take it to be a $\alpha \...
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44 views

Oscillator Strength vs. Dipole Moment

I'm reading "Bose-Einstein Condensation in Dilute Gases" and, in the background chapter (on page 51), the authors introduce the idea of the oscillator strength for a particular transition. The ...
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1answer
35 views

Free space problem in matter [duplicate]

We know that atom is ninety nine percent empty and all matter is made up of matter then why matter is mostly empty ?
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29 views

Is the electron of carbon identical to that of hydrogen? How to prove it? [duplicate]

I am still confused with whether, for example, the electron of carbon is exactly identical to that of hydrogen. How can the scientist confirm this?
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35 views

What is $r$ in angular momentum quantization rule?

We know $$mvr= nh/2π $$ What is $r$ here if I consider positronium system. I suppose it should be the radius of the orbit in which both are moving. But when I take the above equation and electrostatic ...
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295 views

Are orbitals observable physical quantities in a many-electron setting?

Orbitals, both in their atomic and molecular incarnations, are immensely useful tools for analysing and understanding the electronic structure of atoms and molecules, and they provide the basis for a ...
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2answers
114 views

Laser cooling of atoms: more area or more power?

I want to optimise a Magneto-Optical trap. Laser beams come from the the x, y and z directions (positive and negative) and slow the atoms down. Would it be better to increase the beam spot-size (...
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200 views

What does an orbital mean in atoms with multiple electrons? What do the orbitals of Helium look like?

I am wondering about this. It is a familiar sight, the orbital diagrams for the hydrogen atom, depictions of which are abundant and so are not in need of reproduction here. However, what about the "...
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1answer
35 views

What is the reason behind the very high value of nuclear density? [closed]

I know how to arrive at the formula but I want to know it's such a huge number almost 2 X 1017 kg m-3, which is a huge number, all the more surprising to me is that it's a constant! Each and every ...
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1answer
96 views

Does the spin of an electron change when transferred from one atom to another?

Some atoms form bonds when they are given energy to create an excited state.From what I have learnt, every electron is assigned a specific spin quantum number. What I am curious to know,is that, is ...
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406 views

Can an electron gain energy by another electron?

Is it possible for an electron to gain energy from another electron which is jumping from higher energy level to lower energy level, and shifts to higher energy level?
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1answer
52 views

Does the proton wobble due to the electron's orbit in a Hydrogen atom?

In a hydrogen atom the nucleus only has one proton and no neutrons so the electron to nucleus radio is higher for hydrogen than that for any other atom. Does the orbiting electron induce a wobble on ...
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131 views

Are atoms unstable in 4+1 dimensions when quantum mechanics is taken into account?

I understand that in 3+1 dimensions according to classical physics atoms should be unstable however atoms are stable in 3+1 dimensions because the behavior of atoms is governed by quantum physics ...
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57 views

Can one measure experimentally the average distance between the two electrons in the excited state of helium in the singlet versus triplet states?

$\frac{1}{\lvert\ \vec(r_{1})-\vec(r_{2})\rvert}$ is a hermitian operator so I am supposing there could potentially be an observable with this which might be experimentally measured. We can measure ...
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8 views

Discrepancy of capture from 2p+1 state to 2p(+-1)

In the (nlm) characterization of hydrogenic orbitals. Consider the collisions H+ + H(2p+1) ---> H(2p-1) + H+ H+ + H(2p+1) ---> H(2p+1) + H+ where an electron capture has ocurred. Should the ...
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2answers
178 views

Possible inconsistency in Bohr atom model [closed]

It is well known that Bohr model is not totally right. But I recently discovered a very curious inconsistency (if I am right) which I haven't seen explained anywhere. The first postulate of Bohr ...
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1answer
51 views

The point of charge neutrality in the Hydrogen Atom

If we treat the Hydrogen Atom like the Bohr model then we have a proton in the center with an electron orbiting at some radius (the Bohr radius). In this picture you can imagine the electric field ...
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28 views

Bonding Two Cationic Hydrogen Isotopes (protium) yields H2 or He?

If you have two hydrogen atoms. And they are the isotope form "Protium" (1 neutron removed) and they are also cationized +1 (1 electron removed) then you have (in a sense) a single proton (two of them ...
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336 views

Can you breakdown an atom?

Protons, neutrons, and electrons make up the atom, but I've heard that you can't breakdown an atom. How do we know that the electrons, protons, and neutrons make up the atom without being able to ...
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1answer
273 views

Difference between photon upconversion and two photon absorption?

One can find in the wikipedia the following assertion: Upconversion should be distinguished from two-photon absorption However, it is difficult to tell the difference between both processes by ...
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132 views

Characteristic X Ray and Intensity-Wavelength Graph

This is somewhat the kind of graph given in my book. Questions- Q.1- Why is the intensity much higher for the characteristics rays than the continous spectrum? I understand that the wavelengths are ...
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1answer
128 views

Proof for quantized angular momentum [duplicate]

In Bohr's model, Bohr stated that the angular momentum of the electron is quantized and stated that $$L=\frac{nh}{2\pi}$$ So what is the proof for that equation or, in other words, how did he derive ...
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57 views

The force applied by two charges on each other when there is another charge nearby them

QUESTION 1 Let me give two simple scene of charged particles to make you understand my question. There is a fixed positive charged particle in the center. Scenerio 1 : A fixed negative charged ...
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1answer
25 views

Cohesive energy per atom and energy of a single covalent bond

If I have the energy per atom $e=7.37 $eV, how can I estimate the energy of the single covalent bond in the diamond?
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69 views

Applying Bohr model on a system electron and positron [closed]

Consider a hypothetical particle consisting an electron and positron revolving around their common centre of mass. If the Bohr Model is applied on this particle, then find the value of Rydberg ...
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2answers
123 views

How do we decide whether an electron orbital has a non-zero or zero probability of lying inside the nucleus of an hydrogen atom?

How do we decide whether an electron orbital has a non-zero or zero probability of lying inside the nucleus of an hydrogen atom? It is mostly from the radial function, as to what I think but how ...
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1answer
41 views

The counterfactual possibility to explain discrete energies in Thomsons plumpudding model

In the german edition of "Tipler: Physics for scientists and engineers" there i a small text about the plum pudding model of the atom. i give a direct translation: "Thomsons plumpudding model of a ...
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2answers
51 views

When dihydrogen is formed, are photons being emitted?

When a hydrogen in an excited state transits back to the ground state, a photon (or series of photons) is emitted in accordance with the selection rules. When two free hydrogen atoms in the ground ...
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13 views

Detection of the He-nuclei in the historical Rutherford scattering experiment

Which method did Rutherford use to detect the Helium nuclei in his scattering experiment?
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213 views

Can a photon be absorbed by a proton?

When incident light passes through a hydrogen gas, for example, does it have 50% chance (since it's a 1:1 ratio of protons to electrons) of getting absorbed by the proton? Any chance at all? If no, ...
5
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3answers
123 views

What are the original papers on the hydrogen spectral lines?

I am trying to find original sources for experiments that had observed spectral lines from hydrogen or other gases. I am looking into experiments that motivated Niels Bohr to write his ideas on the ...
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1answer
82 views

Is it possible to isolate an individual atom?

I was reading about molecules and wondering about whether they could be individually isolated and "held" or "photographed" in some sense. Google showed that a rubidium atom was isolated, but it left ...
5
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1answer
332 views

Question on Pauli's Exclusion Principle

Pauli's EP says that electrons in a subshell will have opposing spins. Now, lets say I prepare two electrons with spin up. If I took an alpha particle ($\mathrm{He^{2+}}$) and added one of these ...
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1answer
110 views

How is magnetic field created in an atom according to quantum model

How is magnetic field created in an atom according to quantum model? I mean, we are taught about the magnetic field by bohr's model which assumes that electron revolves around the nucleus in a ...
2
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3answers
732 views

Spin and Angular Momentum [duplicate]

What is the difference between spin and angular momentum, are they linked i.e. spin is a form of angular momentum. And is spin what I think it is (the way the electron/particle actually spins)
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1answer
61 views

Emission of Characteristic X Rays

X-rays are emitted when high velocity electrons in an X-ray tube collide with a metal target. Some high velocity electrons on collision with the metal atoms cause an inner electron of an atom to be ...
2
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1answer
195 views

Can an electron jump to a higher energy level if the energy is insufficient or exceeds the ΔE

Lets say we have an atom of hydrogen. It has one electron on E1 = -13.6 eV (E2 = -3.4 eV) energy level. I know that if we fire a photon with 10.2 eV energy the hydrogen atom will absorb it and the ...
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2answers
23 views

Probability of splitting nucleus

I'm sorry if this is a dumb question, but I was just wondering. Say we have a 20 x 20 cm sheet of sulphur, and we have a knife made of iron. If I take the knife, and repeatedly cut the sulphur for an ...
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3answers
106 views

How is the motion of electron in p orbital?

Does an electron in p orbital move around nucleus or move randomly in any individual lobe of p orbital. if it were to move around nucleus then does p orbital move along with it?
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3answers
253 views

How could an s and p subshell occur together in an atom?

s: Subshell of an atom has spherical shape. p: Subshell is a dumb-bell shaped with a node at center of the atom. If we put two shells together they would intersect in an atom. In such a model, ...
5
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3answers
335 views

Are chemical bonds matter?

So it recently blew my mind that chemical bonds have mass. And that a spring that's wound up similarly weights a little more. But there is a distinction between mass and matter. I believe that a ...
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41 views

Nuclear Fusion using magnetic fields

I was wondering if you could use a very strong magnetic field to produce nuclear fusion. The basic idea is a spherical cavity containing Deuterium (and possibly tritium) nuclei whose walls will be ...
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1answer
103 views

How did de Broglie 'fix' Bohr's model?

Bohr's model was created to fix Rutherford's because his model was unstable due to nucleus spiral and so forth. Thus, Bohr postulated three ideas which solved this instability issue. My textbook then ...
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270 views

A Question on Bohr's model of atom [duplicate]

When an electron revolves around a nucleus, It uses its energy in form of kinetic energy and so it release energy and then moves . It means that it release energy continuously, Otherwise, if it does ...