Author Topic: Questions about the Hamiltonian  (Read 4771 times)

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Offline tigeryzz

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Questions about the Hamiltonian
« on: August 15, 2009, 05:28 »
Hi,
I have try to read the informatuions in the.nc files, but i found that the  dimension of Hamiltonian was hard to understand.
As i know, the Hamiltonian should be a matrix which is formated as N*N.  But the dimentions of Hamiltonian cannot be arranged to a matrix.
So, Why and how should i understand the Hamiltonian in ATK?
Thank you!

Offline Nordland

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Re: Questions about the Hamiltonian
« Reply #1 on: August 15, 2009, 09:05 »
Hey Tigeryzz.

The hamiltonian is stored in a super sparse format due to the compact nature of the basis set,
and futhermore it is stored in k-independent format.
Therefore it is far from straight forward how to get k-dependent NxN hamiltonian back,
but I will try to cook up a small example for you.



Offline tigeryzz

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Re: Questions about the Hamiltonian
« Reply #2 on: August 15, 2009, 09:46 »
hi, Nordland,
I have awared that the dimension of the Hamiltonion is depend on different basis set
but in my way, all of thouse are unregular.  :o

Offline zh

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Re: Questions about the Hamiltonian
« Reply #3 on: August 15, 2009, 13:11 »
Please  read "J. Phys.: Condens. Matter 14 (2002) 2745–2779" to understand the dimensions of Hamiltonian matrix.