# [Pw_forum] the problem about eigndisplacement of phonon?

degironc degironc at sissa.it
Tue Jun 6 23:44:21 CEST 2006

针叶 朱 wrote:

> Dear stefano:
> Thank you very much. i still am confused with the equations you give.
> i have three questions:
> (1) \Phi U = M \omega^2 U
> in this equation, what is the meaning of \Phi ?

before answering this question I would like to ear your guess first.

> (2) in fact, what is printed in the matdyn is eigndisplacement. when i
> want eignvector, is M selected to be 207.2 amu. how to renormalize the
> eignvector?