lattice vibrations.

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The characteristics of the elastic vibrational motion of crystal lattice are called as lattice vibrations. In order to understand the vibrations in 1-D(linear) lattice following assumptions are made
(i) All the atoms are arranged on a straight line with constant interatomic spacing 'a'.
(ii) The atoms are identical having same mass 'm'.
(iii) Interaction between the atoms extends only upto the nearest neighbours i.e lattice is characterized by short range forces.(Hooke's law is obeyed)
(iv) Each atom is connected with its neighbours by a massless spring with force constant.

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