How to find electromagnetic force between nucleus and electron?

AI Thread Summary
The discussion centers on calculating the electromagnetic force binding a free electron in graphene to its nucleus, with a focus on the electric field required for ionization. While Coulomb's law is mentioned, participants clarify that ionization energy, approximately 4.5 eV for graphene, is not directly calculable using simple methods. The conversation emphasizes the complexity of determining the necessary electric field or potential for ionization, noting that it involves quantum mechanical principles. Additionally, it is highlighted that the presence of other electrons affects the overall electric field, complicating the calculations further. Understanding these concepts is crucial for accurately assessing the forces at play in graphene's electron dynamics.
Rakib771
Messages
5
Reaction score
3
Hello, I'm new here and honestly I'm not a physics student. I'm studying engineering and so, understand little of physics. I am trying to find the bond force of graphene's free electron. That means, the electromagnetic force by which the electron is bound to the nucleus. I can only calculate it using Coulomb's law but I suppose that wouldn't be correct in this case. So, any help is appreciated.

PS: Another way of simplifying it would be, "How much static electric field is required to detach the electron?"
 
Physics news on Phys.org
That's not something you can calculate simply.

You can try to google "graphene ionization energy" or "graphene work function" to find how much energy is needed to remove an electron from graphene (it turns ou to be around 4.5 eV).
 
DrClaude said:
That's not something you can calculate simply.

You can try to google "graphene ionization energy" or "graphene work function" to find how much energy is needed to remove an electron from graphene (it turns ou to be around 4.5 eV).
Thanks, for the reply. But that is not what I'm trying to find. I'm trying to find the necessary electric field (or potential) to ionize the electron.
 
Rakib771 said:
. But that is not what I'm trying to find.

it is

Rakib771 said:
I'm trying to find the necessary electric field (or potential) to ionize the electron.
you don't ionise the electron, you ionise that atom, by adding/removing energy, to cause it to loose (or gain) the electron(s)

in the case of your graphene, it's 4.5 eVhttps://en.wikipedia.org/wiki/Ioniz...ich,charged atom or molecule is called an ion.
 
eV is a unit of energy, not voltage. Or field.

An order of magnitude estimate is the electron charge divided by the Bohr radius. In real life, an answer is not simple:
  1. This requires a quantum mechanical description of the atom
  2. This requires a quantum mechanical description of the electric field
  3. The other electrons in the atom move in response to the applied field, changing the overall electric field
 
This is from Griffiths' Electrodynamics, 3rd edition, page 352. I am trying to calculate the divergence of the Maxwell stress tensor. The tensor is given as ##T_{ij} =\epsilon_0 (E_iE_j-\frac 1 2 \delta_{ij} E^2)+\frac 1 {\mu_0}(B_iB_j-\frac 1 2 \delta_{ij} B^2)##. To make things easier, I just want to focus on the part with the electrical field, i.e. I want to find the divergence of ##E_{ij}=E_iE_j-\frac 1 2 \delta_{ij}E^2##. In matrix form, this tensor should look like this...
Thread 'Applying the Gauss (1835) formula for force between 2 parallel DC currents'
Please can anyone either:- (1) point me to a derivation of the perpendicular force (Fy) between two very long parallel wires carrying steady currents utilising the formula of Gauss for the force F along the line r between 2 charges? Or alternatively (2) point out where I have gone wrong in my method? I am having problems with calculating the direction and magnitude of the force as expected from modern (Biot-Savart-Maxwell-Lorentz) formula. Here is my method and results so far:- This...
Back
Top