I have an one-body density matrix in a Sine wave basis set (Thus psi = psi*). Unfortunately, these are not the natural orbitals (I have correlated particles), so I have off-diagonal elements. I believe I know how to extract the charge density from this density matrix(adsbygoogle = window.adsbygoogle || []).push({});

[itex]\rho(x;x') = \sum_{ij} c_{ij}\psi_i(x)\psi_j(x')[/itex]

Where x' = x. Can I do something similar to extract a "momentum density"?

[itex]\rho(k;k') = \sum_{ij} c_{ij}\psi_i(k)\psi_j(k')[/itex]

Where k' = k?

Thanks

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# Density matrix in Momentum Space

Can you offer guidance or do you also need help?

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