Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: jccc on 02/08/2014 09:41:07
-
Within the diamond structure, the distance between any two electrons is larger than the distance between any electron and carbon nucleus, if f=kq1q2/r^2 stands.
I cannot imagine such structure in 3d space. It seems logically impossible.
What do you know/think? Thanks!
-
Presumably you are talking about conduction-band electrons?
-
Within the diamond structure, the distance between any two electrons is larger than the distance between any electron and carbon nucleus, if f=kq1q2/r^2 stands.
I cannot imagine such structure in 3d space. It seems logically impossible.
What do you know/think? Thanks!
You are correct that this is logically impossible. You are incorrect in asserting that the electrons have to be farther from each other than from the nucleus. In the case of carbon, there are 6 electrons per nucleus, so there is no way for that statement to be true. I don't see how it would follow from the force equation shown...
-
jccc, density of diamond is ~3.5 g/cm^3
graphite has ~2.1-2.2 g/cm^3
Calculate from this, quantity of atoms in that volume.
Then you can calculate average distances between nucleus.
-
Presumably you are talking about conduction-band electrons?
What kind of band depends on how scientists name it. Just any bond between atoms is mystery to me.
How could electrons get to so close to each other under super strong repulsion force between them?
How could they are so farther away from strong attraction/nucleus?
-
How could we love any stuff we don't understand so much?
Bloody diamond.
-
How could electrons get to so close to each other under super strong repulsion force between them?
The Pauli exclusion principle (http://en.wikipedia.org/wiki/Pauli_exclusion_principle) says that no two electrons can share exactly the same quantum state.
However, one aspect of the quantum state is the spin direction, sometimes shown as spin up & spin down (not to be confused with up & down quarks).
This means that there can be two electrons in each atomic orbital (http://en.wikipedia.org/wiki/Atomic_orbital) (this applies to all elements higher than Hydrogen). This means that the wave function of two electrons frequently share the same volume of space (despite their mutual repulsion).
Maybe someone else could explain how an anti-symmetric wavefunction accomplishes this feat?
-
Let's take a look at gold atom, so many electrons around nucleus, how is another gold atom able to even get to closer? Any two au atoms should repel each other.
Maybe some gluons are escaped from the nucleus? Can we call quantum cops?
-
Let's take a look at gold atom, so many electrons around nucleus, how is another gold atom able to even get to closer? Any two au atoms should repel each other.
Would I not be right in thinking that atoms (as distinct from ions) are neutral, so there would be no net repulsive force?
-
Let's take a look at gold atom, so many electrons around nucleus, how is another gold atom able to even get to closer? Any two au atoms should repel each other.
Would I not be right in thinking that atoms (as distinct from ions) are neutral, so there would be no net repulsive force?
Good morning, Bill.
If atoms are neutral then they will not attract or repel other atoms by EM force, they will only have gravity attraction.
Say atoms are neutral is like to say married couples are sexless, but in fact, they can have group sex at well.
The mystery is the real structure of the atom, why is positive and negative charges not discharge?
Quantum condom?
-
Neutral atoms do not attract each other electrostatically, the way ions would. However, especially with large atoms, like gold, there are still electrostatic forces that attract them (see London Dispersion Force: http://en.wikipedia.org/wiki/London_dispersion_force)
If gold atoms get too close, they will repel (again electrostatics and Pauli exclusion)
However, there is another attractive force that keeps the atoms together in solid or molten states of gold, where the atoms are very close to each other, but not close enough to repel strongly. This force is commonly referred to as "bonding." It is a quantum phenomenon that is responsible for all types of chemical bonding other than ionic bonds (as are found in salts like NaCl or Fe2O3. Essentially, electrons near nuclei can be described as occupying orbitals. These orbitals can be centered on a single atom, or distributed among several different atoms that are close to each other.
Please see: http://en.wikipedia.org/wiki/Covalent_bond http://en.wikipedia.org/wiki/Molecular_orbital http://en.wikipedia.org/wiki/Metallic_bonding
-
Neutral atoms do not attract each other electrostatically, the way ions would. However, especially with large atoms, like gold, there are still electrostatic forces that attract them (see London Dispersion Force: http://en.wikipedia.org/wiki/London_dispersion_force)
If gold atoms get too close, they will repel (again electrostatics and Pauli exclusion)
However, there is another attractive force that keeps the atoms together in solid or molten states of gold, where the atoms are very close to each other, but not close enough to repel strongly. This force is commonly referred to as "bonding." It is a quantum phenomenon that is responsible for all types of chemical bonding other than ionic bonds (as are found in salts like NaCl or Fe2O3. Essentially, electrons near nuclei can be described as occupying orbitals. These orbitals can be centered on a single atom, or distributed among several different atoms that are close to each other.
Please see: http://en.wikipedia.org/wiki/Covalent_bond http://en.wikipedia.org/wiki/Molecular_orbital http://en.wikipedia.org/wiki/Metallic_bonding
So that's how diamond formed?
-
I guess I asked the dumbest question in history.
No scientist is dumb enough to give away the real secret of how to use carbon to make diamond.
They tell you pressure and temperature, smoothy.
-
Yes, temperature and pressure will determine what phase of matter to expect. Every substance (even mixtures of substances) has several phases that it can be in, as determined by the temperature and pressure (not just solid, liquid, gas, supercritical fluid, plasma; but also things like diamond vs graphite--see water as an example: http://upload.wikimedia.org/wikipedia/commons/thumb/0/08/Phase_diagram_of_water.svg/700px-Phase_diagram_of_water.svg.png)
Graphite transforms into diamond at high pressures because the atoms get squeezed closer together. As the nuclei shift, the electronic structure around them changes as well.
In graphite, each carbon atom is bonded to 3 other carbon atoms, and they are all in a plane. Each atom has two electrons that are as low in energy as they can get (1s orbital). The next highest in energy (3 electrons per atom) are shared between two neighboring carbon atoms (one can think of these as sigma bonds), and the highest energy electrons (1 electron per carbon) are free to exist anywhere in the lattice (one can think of these as an extended pi bond or a conduction band).
In graphite, the bonds between carbon atoms are shorter than in diamond, but there are only three atoms bonded to an atom. In diamond there are four carbon atoms bonded to each carbon atom (except at the very edge of the diamond, but let's not think about that here...) The 2-D layers of graphite are not nearly as close to one another as the carbon atoms are to their neighbors within the plane, so as the planes are squeezed together, the highest energy electrons rearrange to accommodate the different geometry. In diamond, all of the electrons are localized to single atoms or the bonds that exist between two atoms (this is why diamond is an excellent electrical insulator while graphite is a good conductor).
It is worth pointing out that diamond does revert back to graphite (very slowly) when the pressure is released.
-
Graphite transforms into diamond at high pressures because the atoms get squeezed closer together. As the nuclei shift, the electronic structure around them changes as well.
How much pressure will be enough to push electrons into nucleus? Isn't between them is 99.9999 empty space and strong attraction force?
You are making circles, empty circle.
I hope we can get school money refund. Do you?
-
It is worth pointing out that diamond does revert back to graphite (very slowly) when the pressure is released.
Diamonds are not "for ever" once the pressure is off; but they stick around long enough to make it seem as though they are.
-
In graphite, each carbon atom is bonded to 3 other carbon atoms, and they are all in a plane. Each atom has two electrons that are as low in energy as they can get (1s orbital). The next highest in energy (3 electrons per atom) are shared between two neighboring carbon atoms (one can think of these as sigma bonds), and the highest energy electrons (1 electron per carbon) are free to exist anywhere in the lattice (one can think of these as an extended pi bond or a conduction band).
Is this a joke? Who seriously believe it? Or it is the best model one can get?
-
No scientist is dumb enough to give away the real secret of how to use carbon to make diamond.
These days, patents are freely available on the web. Try:
Method of making diamonds (http://www.google.com/patents/US2947610)
Method for creating diamonds via detonation by utilizing explosive formulation with a positive to neutral oxygen balance (http://www.google.com/patents/EP2222619A1?cl=en) - this one doesn't apply pressure smoothly!
How much pressure will be enough to push electrons into nucleus? Isn't between them is 99.9999% empty space and strong attraction force?
It takes the pressures found inside a supernova to form a helium, carbon and iron plasma into a neutron star.
-
In graphite, each carbon atom is bonded to 3 other carbon atoms, and they are all in a plane. Each atom has two electrons that are as low in energy as they can get (1s orbital). The next highest in energy (3 electrons per atom) are shared between two neighboring carbon atoms (one can think of these as sigma bonds), and the highest energy electrons (1 electron per carbon) are free to exist anywhere in the lattice (one can think of these as an extended pi bond or a conduction band).
Is this a joke? Who seriously believe it? Or it is the best model one can get?
It explains what we know about graphite, predicts what we found with pyrolytic carbon and graphene, and is consistent with the stereochemistry of all carbon compounds - including diamond. How good an explanation do you want?
As for manufacturing diamonds, there is a market for artificial diamond grit and a limited gem market for clear "GE" diamonds, but they are fairly easily distinguished from the natural product and have little impact on the absurd market for mined gem diamonds.
-
All I care is the real structure of atoms, may carbon or gold or hydrogen.
Besides pulling out quantum laws, no one has an logical answer to:
What force keeps opposite charges apart as electron and proton in atoms?
Isn't force the mechanism for everything?
-
Or is it the best model one can get?
Images of graphene using an atomic force microscope support this model. See here (http://www.google.com.au/imgres?imgurl=http%3A%2F%2Fwww.beilstein-journals.org%2Fbjnano%2Fcontent%2Ffigures%2F2190-4286-3-34-3.jpg%253Fscale%253D2.0%2526max-width%253D1024%2526background%253DFFFFFF&imgrefurl=http%3A%2F%2Fwww.beilstein-journals.org%2Fbjnano%2Fcontent%2F3%2F1%2F34&h=635&w=908&tbnid=lhBdi_Vs38DgNM%3A&zoom=1&docid=N7cGh4-6vLADOM&ei=4RDhU4H1Ocrc8AXEw4KoDg&tbm=isch&ved=0CBoQMygSMBI4ZA&iact=rc&uact=3&dur=1015&page=7&start=117&ndsp=20).
Isn't force the mechanism for everything?
There is a saying in physics that "Anything which is not explicitly forbidden by a law must occur (somewhere)".
Electrons collapsing into protons under human-friendly conditions is explicitly forbidden by the laws of quantum theory.
(For some humorous variations on this saying, see: http://en.wikipedia.org/wiki/Everything_which_is_not_forbidden_is_allowed#National_traditions)
-
Besides pulling out quantum laws, no one has an logical answer to:
What force keeps opposite charges apart as electron and proton in atoms?
Perhaps this is a reason not to discount "quantum laws" ???
-
Besides pulling out quantum laws, no one has an logical answer to:
What force keeps opposite charges apart as electron and proton in atoms?
Perhaps this is a reason not to discount "quantum laws" ???
If that's your way of science.
You win again. Dear Friend.
The electron is super lonesome, the proton is extra honny. They love each other more than ANYthing.
Why is your God forbidden them to make love?
-
So what's the answer to this simple question?
Is this a real science forum?
Am I dreaming?
-
All I care is the real structure of atoms, may carbon or gold or hydrogen.
But you have asked for an explanation of the structure of a compound, not an atom.
Besides pulling out quantum laws, no one has an logical answer to:
What force keeps opposite charges apart as electron and proton in atoms?
Quantum laws. Logic, as perceived by most people, has very little to do with the reality of atomic physics.
Isn't force the mechanism for everything?
No. It's a macroscopic summation of the real mechanisms.
In science you have to start with what is, not what you think ought to be, and then work out how reality works.
Now let us suppose that we have six electrons that "want to be" as far from each other as possible, but in some way disposed around a nucleus. It turns out that two can occupy a spherically symmetric orbital, with paired spins. Now we need to distribute four in some sort of symmetry (because a symmetric structure will have the lowest energy). But there are other carbon atoms nearby, each with four outer electrons. So we can construct a 3-dimensional lattice in which pairs of electrons with opposite spins occupy orbitals aligned with the axes of tetrahedra with a nucleus at the center of each tetrahedron, and voila, diamond.
Alas, this simple explanation involves paired spins, which is a quantum mechanical concept. However given that elementary quantum mechanics is over 100 years old and part of the school syllabus, I think we can be forgiven for using it. Especially as no other explanation works.
-
100 years is nothing. Theory/reality can be wrong for thousands years. For example, we use fire to smoke tobacco till this invented
Are we even sure that there are 6 electrons in a carbon atom?
-
Yes. If there were more or less, it wouldn't be carbon. And don't confuse theory with reality: science is not religion.
-
Yes. If there were more or less, it wouldn't be carbon. And don't confuse theory with reality: science is not religion.
How do you count 6 electrons? What is reality? QM?
-
You can ionize carbon atoms with radiation. Up to six electrons can be removed, leaving a nucleus with a charge of +6. That is how we can experimentally verify there are six electrons.
It is also a definitional thing. It is carbon because there are six protons in the nucleus. To be a neutral carbon atom, it must have six electrons.
-
You can ionize carbon atoms with radiation. Up to six electrons can be removed, leaving a nucleus with a charge of +6. That is how we can experimentally verify there are six electrons.
It is also a definitional thing. It is carbon because there are six protons in the nucleus. To be a neutral carbon atom, it must have six electrons.
If that's true, please show me the test/source?
-
This is the first paper I found without a pay wall that experimentally demonstrated sequential ionization of carbon atoms: http://www.iaea.org/inis/collection/NCLCollectionStore/_Public/07/276/7276215.pdf
Most of it is in Russian, but even if you can't understand Russian there is an English summary on the 4th page, and most of the tables and figures are understandable.
-
Yes. If there were more or less, it wouldn't be carbon. And don't confuse theory with reality: science is not religion.
How do you count 6 electrons? What is reality? QM?
Reality is what happens. Quantum mechanics is how we understand and predict what happens. Read up on Moseley and the determination of atomic number.