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zrqiao / 2018QC-Project-Ab-initio-wavefunction-program

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Atomic mass #3

Open k9cdt opened 6 years ago

k9cdt commented 6 years ago

In the current version of the C++ headers, the atomic mass is the mass of the whole atom, instead of the nuclear. I'd like to mention the following facts so please reconsider if these constants works robustly.

  1. In electronic structure problems, the nuclear mass has no effect on the calculation.
  2. These mass are masses of whole atoms, not the nuclear alone. The total mass of the atom is consisted of three parts: the mass of the nuclear, the mass of the electrons, and the effective mass of the interaction between nuclear and the electrons. So when doing dynamics, make sure you understand these differences.
  3. The mass of the nuclear is not equal to the sum of massed of the protons and the neutrons that form it. Approximating the total mass as the sum of the these particles incurs about 5% error.
Nymphet commented 6 years ago

thank you. i just copied the masses from psi4 and i didn't really look into that. i'll add the nuclear masses later

k9cdt commented 6 years ago

You will find it almost impossible to get the data.

btw, look into the physics before you commence on it. Perhaps I am totally wrong about the masses. Anyway, I think these features are to finish only after we finish the SCF part. Let's suspend it.