Recent content by thuong

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    Graduate Understanding Dangling Bonds and Hydrogenation of Surfaces

    Hi Sara, Could you pls tell me the papers you have read...? Bests,
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    Graduate Hartree-Fock vs density of charge

    Thanks
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    Graduate DFT vs Van de Waals: Explaining the Difference

    Thank you very much!
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    Graduate DFT vs Van de Waals: Explaining the Difference

    Hi everybody, Can you tell me, in general, why Density Functional Theory does not describe the Van de Waals interaction? Many thanks,
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    Graduate Deriving equation to describe lattice vibrations of a one dimensional crystal

    We can derive the fomula V(r) = V(a) + (1/2)(d^2V/dr^2)(r-a)^2 + ... as follow: We write V(r) = V(r - a + a) where a is the equilibrium position of a particle. We assume that the displacement of the particle with respect to the equilibrium position is very small, so we can expand...
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    Graduate Biased nanoelectronic device simulation

    Time-dependent DFT can describe quantum transport in some molecular devices. For traditional FET, my last post can be the answer, in this case, DFT is very tough!
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    Graduate Biased nanoelectronic device simulation

    Hi, This might help http://www.koders.com/ However, you can write a simple code by solving Possion and Schrödinger equations self-consistently. Bests,
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    Graduate Hartree-Fock vs density of charge

    Hi all, If density of electron is high, Hartree-Fock approximation will work well under what conditions? What if the density is low? Thanks