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0answers
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+50

Plasmon quenching vs plasmon decay. What is the difference?

I'm reading an article "Quenching, Plasmonic, and Radiative Decays in Nanogap Emitting Devices" (pubs.acs.org/journal/apchd5). I don't understand the following: Counterintuitively, we evidence ...
0
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0answers
10 views

Methods for producing Molecular C60 (A.K.A Buckminsterfullerene) [on hold]

I wanted to know about how to produce molecular C60 - also known as Buckminsterfullerene/buckyballs. I read online that vaporising graphite in helium gas was how scientists initially discovered ...
3
votes
2answers
34 views

Creasing of a material at the molecular level

What exactly happens when a material (particularly paper or even cloth or a metal) is folded to form a crease? Why is it that a creased material tends to retain form, while a lightly folded one, ...
2
votes
1answer
136 views

Thermionic emission, delayed emission and predissociation

In molecular photodissociation, the thermionic emission, delayed emission and predissociation are the same? Otherwise, what is the difference between them? My question is not about the solids, but I ...
0
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2answers
345 views

Resonate frequency of an object?

Below is a paragraph taken from the web site, physicsclassroom.com: It is often useful to think of these electrons as being attached to the atoms by springs. The electrons and their attached ...
0
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0answers
16 views

Application of the Mean Field Approximation for molecules

When I studied the Ising Model in a course on Statistical Physics one approach that was presented was to use the Mean Field Approximation. In the ocasion I've noticed that it is also called "molecular ...
5
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5answers
773 views

Why is quantum physics needed to explain photosynthesis?

Why is quantum physics needed to explain photosynthesis? In what aspect does the corresponding classical theories for photosynthesis fail?
2
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1answer
137 views

induction of van der Waals forces

Is there a way to maximize van der Waals forces between two materials, by electrifying one material, thus creating dipoles/instantaneous dipoles and thus creating stronger van der Waals forces? has ...
0
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1answer
118 views

Do solids have translational energy?

Along with having vibrational energy, do both crystalline and amorphous solids also have translational energy? I ask because I've always understood solids to have just vibrational motion/energy. But ...
3
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1answer
104 views

Finding Electronic Energy Levels by Representation Theory

Let $$u=\left( \begin{array}{cccc} c_1&c_2&c_3&c_4 \end{array} \right)^T$$ for $$\psi = c_1\psi_1 + c_2\psi_2 + c_3\psi_3+ c_4\psi_4$$ We assume that $\left<\psi_i|\psi_j\right> = ...
0
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0answers
14 views

Average Rate of Evaporation of Water

Consider a container of volume $V$ and cross sectional area (exposed to another fluid, say air) $SA$. The container is at constant temperature $T$, and contains $N$ molecules of water, where $N$ is ...
0
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2answers
2k views

Thermal Velocity

What is thermal velocity? What is it's physical significance? Wikipedia says: The thermal velocity or thermal speed is a typical velocity of the thermal motion of particles which make up a gas, ...
0
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2answers
42 views

Do homonuclear diatomic molecules interact with infrared light?

A molecule will appear on IR spectra if its dipole moment changes during vibration. Due to symmetry, the dipole moment of homonuclear diatomic molecules ($\mathrm{H_2, N_2, O_2, F_2, \dots}$) is zero. ...
3
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1answer
484 views

Wigner Threshold law in Photodetachment and Photoionization

I am writing this question here because I have a problem in understanding the Wigner Threshold law in Photodetachment and Photoionization. The Wigner Threshold Law is given by: $\sigma$=$E^{L+1/2}$. ...
1
vote
1answer
331 views

Why is the orbital angular momentum of a pi electron along the axis of two atoms' molecule one?

I'm reading quantum chemistry. The book says that the orbital angular momentum of a $\pi$ electron along the symmetry axis of a molecule made up of two atoms is $\pm 1$. I think this is a primary ...
1
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1answer
707 views

Bimolecular recombination in few words

I'm making a short seminar about VERY broad topic of fullerenes in photovoltaics, but I'd like it to be educational (not just full of words hard to audience to make them think I'm smart). In one of ...
3
votes
0answers
37 views

If 2 fermionic atoms form a molecule, will the molecule always behave as a boson?

2 fermionic atoms give a bosonic molecule. 2 bosonic atoms form a bosonic molecule. Is there a energy scale where these two molecules will behave differently? If yes, will it depend on the ...
1
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1answer
54 views

Any Antimolecule so far?

As i've been reading on Wikipedia, we are artificially able to join an antiproton with a positron to form an antihydrogen. But if i search for antimolecule, i can't find any results on that, only a ...
0
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1answer
32 views

Neutron scattering off molecules

From neutron scattering off molecules it is possible to get information about molecules' geometry. Given the size of a particular molecule, what are the criteria for choosing the wavelengh of the ...
0
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1answer
60 views

Can two different objects or system of molecules have different temperatures, but having same internal kinetic energy?

If I take an extreme case, where a body has only an internal potential energy with zero internal kinetic energy, does this body have a temperature? Another question related to it: if two objects A and ...
5
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3answers
276 views

What is the difference between the shapes of molecules with different isotopes

I'll explain my question on example of water molecule. Let us have three water molecules: normal water $H_2 O$, heavy water $D_2 O$ and semiheavy water $HDO$. Is there any difference between the ...
3
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0answers
134 views

Is the translational information all that matters, or do we need to take into account internal states?

For anyone in this community that's familiar with quantum teleportation, I need desperate help. I am currently working on my senior thesis and my goal is to teleport a molecule. Background: So in ...
0
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1answer
50 views

Atomic number of $\rm CO_2$? [closed]

I have to calculate the Bethe-Bloch equation for a $\rm CO_2$ absorber, I know this is a stupid question, but is Atomic number additive? Or do I need to do something a little more complex? I was ...
1
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3answers
526 views

Sound as a use to separate molecular structures

Sound can be a destructive force. However, could it be used to separate say the Hydrogen atom from the Oxygen atoms?
1
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0answers
28 views

Why do very small balls attached to a tiny spring propel themselves in hardly moving fluids? [duplicate]

I recall watching a youtube video about a ball with a spring on the idea propelling themselves through stable fluids without any assistance, even if we make sure the spring isn't moving in the ...
6
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0answers
99 views

How do proteins perform their function? [closed]

Let's, for example, take a ribosome. It is an enzyme that is in turn just a molecule that must follow the laws of physics. Correct me if I'm wrong, but it can be looked upon as a molecular machine ...
6
votes
3answers
7k views

What is the resonant frequency of liquid water?

I learned it's not 2.45 GHz. But what is it, then? In my failure to find the real value, I'm starting to wonder: does it even make sense talking about a resonant frequency of water molecules?
1
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1answer
30 views

Does less heat equals more reflexion? [duplicate]

Does colder metal reflect more if hotter metal reflect less? Why?
0
votes
1answer
34 views

can odorous VOCs be removed by an ionizing air purifier? [closed]

I am considering replacing my IQAir HealthPro 250 air purifier by an Electrolux EAP300. According to the marketers, the EAP300 has PlasmaWave(TM) technology that supposedly removes odours from the air ...
0
votes
0answers
29 views

how can VOC filters work given that atmosphere has 1800 ppb methane?

I have an IQAir HealthPro 250 air purifier that has a 2.5 kg activated charcoal volatile organic compound (VOC) filter. According to the manufacturer, the replacement interval is from 12 to 24 months. ...
0
votes
3answers
149 views

Why is alcohol less dense than water?

Ethyl alcohol (ethanol) is less dense than water, and it's boiling point is lower. But this molecule is more complex and bigger than the simple H2O. How can a substance with a higher molecular size ...
2
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0answers
37 views

Why is CO a good tracer for H2? How are those molecules correlated?

One always reads and hears that CO is a good tracer for H2. How are they correlated? How can you deduce from the (measurable) CO the amount of the (unmeasurable) H2 in the ISM?
-2
votes
2answers
126 views

Can $CO_2$ be separated into $C$ and $ O_2$?

I'm doing a little bit of research for an experiment that I want to conduct in science and it relies on that one question. So, Is it possible to separate a $CO_2$ molecule into a $C$ and $O_2$? ...
3
votes
1answer
51 views

How do molecules absorb heat?

How do molecules absorb and retain heat, and how is that heat able to still affect nearby molecules? On Venus there is a green-house effect where the large, dense Carbon-Dioxide atmosphere absorbs ...
4
votes
2answers
90 views

Mountains and their local effects on Earth's gravity

I was once a truck driver and can feel the inertia and kinetic energy on heavy loads while traveling. While climbing mountains in the Rockies I noticed gravity was different on the side of the ...
0
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1answer
57 views

Atoms Inside a Lightning Bolt

What happens to atoms trapped in lightning? Why do electrons not split an atom but can change them inside the bolt? Can atoms travel on a bolt?
0
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1answer
57 views

How to determine rotational energy of gas molecules

For an arbitrary polyatomic molecular gas, what is the expected behavior of $U_{rot}(T)$, the rotational kinetic energy of the atoms, in the two limits T high and T low? So far, I have written an ...
0
votes
1answer
47 views

How can I determine the vector parallel to the long molecular axis?

I have a molecule in a system (the molecule is not in the center) with determined coordinates of all atoms. One of my molecule is on the picture below What I need is to determine the vector that ...
2
votes
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 ...
1
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1answer
63 views

Is (or why isn't) static charge as lethal as ionizing radiation?

Ionizing radiation, e.g. the "stuff" emitted by radioactive materials, is dangerous to humans since changes to the electron configurations (in the human body) causes the various molecules (in the ...
0
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3answers
65 views

Splitting molecule

The photon reacts with the binding electrons orbiting the two atoms. The photons have the 'correct' wavelength for Bond Dissociation Energy (BDE). 'Splitting' the molecule involves applying the ...
3
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4answers
1k views

How to determine what an object is composed of?

Heads up: This question has never been asked (here) before the way I will ask it here, so let's shed some light on it a bit. Prelude and anecdote(can be skipped): The other day I was walking home, ...
0
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2answers
295 views

How are bond angles determined?

Electron microscopes cannot clearly depict the exact shape and structure of atoms and molecules, even though it does show a vague, cloudy image. In my AP chemistry class, I learned that the bond angle ...
0
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2answers
286 views

Unknown magnetic moment of orthohydrogen

Conforming to present atomic physics, the two elementary particles in hydrogen atoms can have either parallel or antiparallel magnetic moments, and the energy differences between these two kinds of ...
0
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1answer
74 views
2
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1answer
2k views

Degrees of freedom in a diatomic molecule [duplicate]

We know that a monatomic compound can only have 3 degrees of freedom as we can consider it to be a point mass. However now that we consider a diatomic molecule, there are 3 degrees of freedom in ...
0
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0answers
12 views

Can the atomic vibration of molten liquids be decomposed into a superposition of a series of normal modes?

From what I've learned, molten liquids have short-range periodicity (short-range doesn't just apply to the amorphous solid state/glassy state). So does this mean that, along with amorphous solids, the ...
2
votes
1answer
82 views

Why titanium “writes” on glass , meanwhile don't scratching it?

It is possible to "write" on a piece of glass with a bar of titanium without scratching the glass. I think the explanation is that molecular connections in glass are stronger than in titanium and ...
2
votes
3answers
177 views

What happens to the $PV=nRT$ formula as the gas enters the liquid phase?

The formula $PV = nRT$ explains the relationship between pressure, volume and temperature in terms of the quantity of gas present in a container. I'm trying to understand how these are related once ...
0
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0answers
35 views

Can a buckyball gun be fired by observing it?

If a buckyball was placed inside a gun made from maybe a carbon nanotube or something, would measuring the momentum of the buckyball cause the the gun to fire? At what speed would the buckyball exit ...