Recent content by Eduard1

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    Finding Components of Vectors in a Crystal Lattice

    Homework Statement Be the vectors a, b, c such as: | a | = | b | = | c | = 10.5 Angstron The angles between these vectors are: alpha = beta = gamma = 109.5 degree These vectors represent the lattice vectors of a crystal. Find out their components (a_1, a_2, a_3, b_1...
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    We have that for a crystal the lattice parameters

    Homework Statement We have that for a crystal the lattice parameters (in angstrom and degree) are: a b c (in Angstrom) 10.5 10.5 10.5 \alpha β γ (in degree) 109.5 109.5 109.5...
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    Is WKB or Perturbation Theory More Applicable for Slowly Varying Potentials?

    Hi Bob, Thanks a lot for the answer. It actually helped me to clarify the problem. Ed
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    Is WKB or Perturbation Theory More Applicable for Slowly Varying Potentials?

    Dear Bob, Thanks a lot for the fast answer. If I do not bother you too much could I ask you which is the difference between "smooth" and "small" potentials. By smooth potential I would understand something like the potential in a metal (i.e. free electron system). But this is also...
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    Is WKB or Perturbation Theory More Applicable for Slowly Varying Potentials?

    Dear All, I have recently read about WKB approximation and about perturbation theory. Both methods are applicable in the range of slowly varying potentials. What I have not understood is which is the range of applicability of one of the method compared with the other one. More...