Why do we use Local field correction?

  1. Knowing the dielectric constant of a medium we can earn the electric field at any point in that medium which is deferent from the applied external electric field. So why do we use the Local field correction?
     
  2. jcsd
  3. mfb

    Staff: Mentor

    The dielectric constant is a macroscopic quantity - you get this value if you average the effects of many atoms/molecules. If you look closer, you might find small deviations from that average.
     
  4. Meir Achuz

    Meir Achuz 2,061
    Science Advisor
    Homework Helper
    Gold Member

    There are huge differences from the average.
    E gets huge and changes sign near atoms.
     
  5. DrDu

    DrDu 4,461
    Science Advisor

    You can include local field corrections by working with a dielectric function which includes spatial dispersion. In the case of a homogeneous medium, this means that epsilon is a tensor which depends on frequency omega and wavevector k.
     
  6.  
  7. DrDu

    DrDu 4,461
    Science Advisor

    I wrote dielectric function instead of dielectric constant as the effects cannot be included in a single number.
     
Know someone interested in this topic? Share this thead via email, Google+, Twitter, or Facebook

Have something to add?