How close can 2 atoms get?
When I touch a wall I know I'm not really "touching" the wall since the wall is made of atoms like me so the electrons on the outside of the wall's atoms repel the electrons on the outside of my atoms.
So its more like I'm touching a force field around the wall correct? And there's one around me?
Do we know the size of this field? Under normal circumstances how close can 2 atoms be? What about when they react chemically or nuclearly?
It depends upon how hard you push. The field strength varies as a function of distance. The strength of the field is equal in magnitude to the force you apply plug the value of that force into the equation for the strength of an electric field and solve for the radius. I recommend looking up the normal force and how it relates to particle physics
>Under normal circumstances how close can 2 atoms be
take a cup of water, that'll give you an idea since water is nearly incompressible
if you touched something hard enough you're hand will just be cold welded to that thing
Computational chemist here. We can apply methods that we know to be highly accurate around the equilibrium distance of the two atoms from comparison with experiment. Short of basis set issues (which are solvable), there is no reason to not trust those numbers. So yes, it can be calculated, and it turns out to be roughly exponential. The term we use is Pauli repulsion.
Most of the time, we don't really care about this part, though, it only needs to be repulsive and give a decent equilibrium distance. The other side of the potential is much more interesting.
>>7712231
>When I touch a wall I know I'm not really "touching" the wall since the wall is made of atoms like me so the electrons on the outside of the wall's atoms repel the electrons on the outside of my atoms.
But what is "really touching the wall" then? Atom cores "touching"? And what does that even mean, it's not like they're little plastic balls
>>7712288
Unrelated question but you said you were a computational chemist. I'm curious how much computer science computational scientists learn. Do you know basic algorithms and data structures? Can you solve recurrences for divide-and-conquer algorithms? Etc. What computing classes did you take, basically?
If I can not touch anything, why touching water (or paint) makes my hand wet (or coloured)?
>>7712300
Haha, way too little, as I am finding out trying to switch to industry as a programmer. Despite 4 years experience in C++ and a PhD. You may have a look at PSI4 or NWCHEM, those are open-source quantum chemistry codes. Yes, we know a bit about algorithms, but a lot of what we do is matrix manipulation and LinA or integral calculation via numerical stuff. Not that interesting if you build Apps for whatever. In terms of classes: on-the-job training and as part of the quantum chemistry training, i.e. not by CS people, but QC people.
>>7712314
It's called a non-covalent interaction. The 'touch' word does not really apply in chemistry.
>>7712231
Under normal circumstances? Technically, atoms get so close that they fuse together in stars, and since I think those probably take up a considerable amount of the mass of the universe, then normally, they get that close.
>>7712292
You have to get past neutron degeneracy to REALLY be touching.
>>7712344
So if the paint soils my finger it's because atoms/molecules are electrified by touch?
>>7712231
It depends on what you mean by touching. They could fuse if you get them close enough to have the Strong Force kick in.
>>7712288
I want to break into computational chemistry to study ancillary questions to pharmaceuticals, natural products, and enzymatic synthesis, particularly to model receptor-ligand interactions for drug discovery and perhaps design of novel enzyme catalysts (then realized through recombinant microbes) for greener, more efficient lab and industrial scale synthesis. Other than becoming really solid on quantum chem and reading a book like Bachrach, do you have any advice for me?
>>7712288
So when I touch a wall, just pressing on it with average pressure not like trying to push the wall over or something, how close are the atoms in my hand to the atoms in the wall? Can we put an actual value on that or not? Am I 0.000000000000000001 nanometers away from it or something? Is there a number/measurement that can express it and if so what? Thats what I want to know.
>>7713288
At these scales, your hand's atoms and the wall's atoms aren't really solid things. They're waves. There's no well-defined boundary where your hand ends and the wall begins. "Touching" is poorly defined on atomic scales.
>>7713307
OK so we can't say exactly how far the nuclei of my hands atoms are from the nuclei of the wall's atoms. Thank you that's what I was curious about.
Tfw nobody on /sci understands nuclear fusion
There is no limit buddy
ITT Fucktards cant give a straight answer.
>>7713378
Electrostatic repulsion is the overwhelming force that is rather hard to overcome, but once you get within a certain radius the nuclear forces take over and the net force is attractive, so nuclear fusion happens. This is because electrostatic force dies relative to r^2 but nuclear force dies relative to e^-something*r (cant remember exactly) but is much stronger in the small radius where it is relevant. So basically, theres no limit as to how close you can get two atoms, but if you get them close enough they will undergo fusion
>>7713785
you can calculate the closest you can get two atoms before fusion occurs on http://nrv.jinr.ru/nrv/webnrv/qcalc/ by selecting fusion, entering the two atoms, and looking under "barrier position"
>>7713792
And? Just because the atoms fuse doesn't mean they are touching.
Are protons and neutrons "touching?" No, they're made up of quarks the same way atoms are made up of protons and neutrons. You can compress them farther, with enough force.
"Touching" means the distance between two objects cannot be made smaller.
The only place this is true is in the core of a blackhole, after electron degeneracy pressure and neutron degeneracy pressure have been overcome by the gravitational force.
https://youtu.be/P0TNJrTlbBQ
I really really like this video. This is /thread
>>7713288
I'm so sorry this thread is full of over educated idiots. You're hand is about 0.1 nanometers away from the wall.
Honestly, the reason the public is confused/missinformed on things like global warming to every other fucking thing under the sun is because of scientists who can't communicate.
Shame on you.
>>7714416
Shame on you Sci
For shame
>>7714552
if you don't know quantum mechanics, you can't really even understand how to manipulate the quantum chemistry codes to simulate what you want.
Quantum Chemistry is just a bunch of chemists that learned some quantum mechanics and some programming and just manipulate the codes of physicists work.
>>7714283
>"How close can two atoms get"
>"just because they become one atom doesn't mean they are touching"
>"the protons and neutrons aren't 'touching'"
at that point, the question should be "how close can you get subatomic particles," not two atoms. Also,
>"they can be compressed further"
what are quantized energy levels hurr durr
>when i am touching myself, i am not touching myself
>i am jerking off the force field of muh dick
fuck science, its better to be ignorant and enjoy life subjectively
