following what is AIM
The AIM paper was written by Robert G. Parr(PPP, b3lyP), Paul W. Ayers(P's PhD student), and Roman F. Nalewajski(information theory expert)
Robert G. Parr worked with a lot of big names and is big by himself. Now is trying to view DFT from viewpoint of information theory(IT, not technology :)). One more paper (http://www.pnas.org/cgi/reprint/97/16/8879.pdf)
Interview with Professor Robert G. Parr
http://www.quantum-chemistry-history.com/Parr1.htm
A: After your life long interest, how do you view electron density now?
P:"...
Electron density is electron density. It sticks there through all levels of orbital theory. I mean, you could include as complicated a wave function as you could imagine to get a very accurate answer. And you wouldn't be able to understand that in any helpful terms.
But the electron density is electron density which changes very little from approximation to approximation.
A remark that should be made, and the case is strong, that the Kohn-Sham method is closer to all of the correct physics than the Hartree-Fock method is.
I have already mentioned one aspect, the highest orbital energy in Kohn-Sham is the exact {pronounced with emphasis} ionization potential, not the approximate ionization potential.
The Hartree-Fock operator is non-local, the Kohn-Sham is local, like the Hamiltonian operator. Another one is - believe it or not - every orbital in Hartree-Fock theory has got the same long range tail. Even a one s-orbital has the same tail as a 6f-orbital in some heavy atom. In Kohn-Sham theory the orbitals have their own tails.
The difference of excitation energies is more cleanly, or maybe not more cleanly, but more accurately connected to the excitation energy in Kohn-Sham than that in Hartree-Fock.
Hartree-Fock is really quite non-physical compared to Kohn-Sham and it can be argued that the Hartree-Fock determinant should be thrown away in favor of the Kohn-Sham determinant as the prime tool of the description in chemistry (as it already is in physics).
..."
Roman F. Nalewajski
Information Theory of Molecular Systems (Hardcover)by Roman F. Nalewajski (Author)
http://www.amazon.com/Information-Theory-Molecular-Systems-Nalewajski/dp/0444519661/ref=sr_1_1/105-5607062-2462847?ie=UTF8&s=books&qid=1194478845&sr=1-1
Robert G. Parr worked with a lot of big names and is big by himself. Now is trying to view DFT from viewpoint of information theory(IT, not technology :)). One more paper (http://www.pnas.org/cgi/reprint/97/16/8879.pdf)
Interview with Professor Robert G. Parr
http://www.quantum-chemistry-history.com/Parr1.htm
A: After your life long interest, how do you view electron density now?
P:"...
Electron density is electron density. It sticks there through all levels of orbital theory. I mean, you could include as complicated a wave function as you could imagine to get a very accurate answer. And you wouldn't be able to understand that in any helpful terms.
But the electron density is electron density which changes very little from approximation to approximation.
A remark that should be made, and the case is strong, that the Kohn-Sham method is closer to all of the correct physics than the Hartree-Fock method is.
I have already mentioned one aspect, the highest orbital energy in Kohn-Sham is the exact {pronounced with emphasis} ionization potential, not the approximate ionization potential.
The Hartree-Fock operator is non-local, the Kohn-Sham is local, like the Hamiltonian operator. Another one is - believe it or not - every orbital in Hartree-Fock theory has got the same long range tail. Even a one s-orbital has the same tail as a 6f-orbital in some heavy atom. In Kohn-Sham theory the orbitals have their own tails.
The difference of excitation energies is more cleanly, or maybe not more cleanly, but more accurately connected to the excitation energy in Kohn-Sham than that in Hartree-Fock.
Hartree-Fock is really quite non-physical compared to Kohn-Sham and it can be argued that the Hartree-Fock determinant should be thrown away in favor of the Kohn-Sham determinant as the prime tool of the description in chemistry (as it already is in physics).
..."
Roman F. Nalewajski
Information Theory of Molecular Systems (Hardcover)by Roman F. Nalewajski (Author)
http://www.amazon.com/Information-Theory-Molecular-Systems-Nalewajski/dp/0444519661/ref=sr_1_1/105-5607062-2462847?ie=UTF8&s=books&qid=1194478845&sr=1-1
Labels: AIM, people, Robert G. Parr
posted by chao at 3:30 PM
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